Explanation / Rationale

a) Is not correct. A member without a missed deadline can get a discount and a gift T-Shirt after 15 bicycle rentals
b) Is not correct. A member without a missed deadline can get a discount but no gift T-Shirt until they rented a bicycle 15 times
c) Is not correct. Non-members cannot get a discount, even if they did not miss a deadline yet
d) Is correct. No discount as a non-member that has also missed a deadline, but only members can receive a gift T-Shirt. Hence, the action is not correct

Explanation / Rationale

a) Is not correct. Usability testing is business facing testing that critiques the product (Q3)
b) Is not correct. Functional testing is business facing testing (Q2)
c) Is not correct. User acceptance testing is business facing testing that critiques the product (Q3)
d) Is correct. Component integration testing is technology facing testing that supports the team (guides the development) (Q1)

Explanation / Rationale

a) Is not correct. Collaborative user story writing means that all stakeholders create the user stories collaboratively, to obtain the shared vision
b) Is correct. Collaborative user story writing means that all stakeholders create the user stories collaboratively, to obtain the shared vision
c) Is not correct. Collaborative user story writing means that all stakeholders create the user stories collaboratively, to obtain the shared vision
d) Is not correct. This is the list of properties that each user story should have, not the description of the collaboration-based approach

Explanation / Rationale

Given the following description of test analysis:
To identify the features that require testing, the test basis is analyzed and defined as test conditions, which are then prioritized along with related risks. The systematic identification of test conditions as coverage items often involves using test techniques both during test analysis and as part of the test design activity.
From the above description, it can be seen that test techniques are often used in the test analysis and test design activities. Boundary value analysis and equivalence partitioning are test techniques.
a) Is not correct. Test implementation is not likely to involve the use of test techniques as it is mostly concerned with assembling test cases into test procedures, while test techniques create test cases
b) Is correct. Test design is likely to involve the use of test techniques to create test cases from test conditions and coverage items
c) Is not correct. Test execution is not likely to involve the use of test techniques as it is mostly concerned with executing test procedures (and so test cases), while test techniques create test cases
d) Is not correct. Test monitoring is not likely to involve the use of test techniques. Test monitoring is mostly concerned with ongoing checks to ensure the plan is being followed, while test techniques create test cases
e) Is correct. Test analysis is likely to involve the use of test techniques to identify test conditions

Explanation / Rationale

The following three transitions:

“REQUESTING -> CONFIRMED”
“WAITING LIST -> CONFIRMED”
“WAITING LIST -> END”

cannot appear in the same test case, which suggests that at least three test cases are required. All the other transitions can appear in combination with one or more of these three transitions, so we need a minimum of three test cases. In fact, only three sequences are possible:

TC1: START (Room request) → REQUESTING (Available) → CONFIRMED (Pay) → END
TC2: START (Room request) → REQUESTING (Not available) → WAITING LIST (Available) → CONFIRMED (Pay) → END
TC3: START (Room request) → REQUESTING (Not available) → WAITING LIST (Cancel) → END

Thus:
a) Is correct
b) Is not correct
c) Is not correct
d) Is not correct

Explanation / Rationale

In branch testing the coverage items are branches, which are represented by the edges of a control flow graph. There are 8 edges in the control flow graph.
Thus:
a) Is not correct
b) Is not correct
c) Is correct
d) Is not correct

Explanation / Rationale

Let us refer to the transitions with E1, …, E5 as in the picture. The variable N denotes the number of elements currently stored. Each “Add” event increases it by 1, and each “Remove” event decreases it by 1. Notice, that when the “Add” event occurs while being in the NOT FULL state, the state changes to FULL only if N=2. If N<2, the system stays in the NOT FULL state. If N=0, no “Remove” action is possible. Similarly, if N=3, no “Add” action is possible.

Test a) can be written as E1, E3, E3, E2, E4 (so covers 4 out of 5 valid transitions, achieving 80% valid transitions coverage).
Test b) is infeasible, because after the first three “Add” actions the system is in the FULL state and there is no valid transition going from FULL triggered by the “Add” event. After the first three transitions only 60% of valid transitions coverage is achieved.
Test c) can be written as E1, E2, E4, E5, E3 (so covers 5 out of 5 valid transitions, achieving 100% valid transitions coverage).
Test d) can be written as E1, E2, E4, E5, E4 (so covers 4 out of 5 valid transitions, achieving 80% valid transitions coverage).

Thus:
a) Is not correct
b) Is not correct
c) Is correct
d) Is not correct

Explanation / Rationale

a) Is not correct. We do not accept the risk; concrete actions are proposed
b) Is not correct. No contingency plans are proposed
c) Is correct. The proposed actions are related to testing, which is a form of risk mitigation
d) Is not correct. Risk is not transferred but mitigated

Explanation / Rationale

a) Is not correct. The benefits of retrospectives include team bonding and learning from sharing issues, and better collaboration between developers and testers through reviewing and improving working practices. Calling out individuals who a team member may feel did not fully contribute to achieving quality as required by the whole-team approach will not contribute to this team bonding and collaboration
b) Is correct. During the retrospective, the group discusses what aspects of the project were successful and should be retained, as well as areas that could be improved, and how to do so
c) Is not correct. The benefits of retrospectives are based on increased effectiveness and efficiency through process improvements; they are not an opportunity to let off steam and criticize management and customers. Also, the results are recorded, usually in the test completion report, so anything said in the meeting could be read by other stakeholders
d) Is not correct. Retrospectives are meetings that are typically held at the end of an iteration where team members will focus on discussing quality-related issues that have occurred in the current iteration. They are not used for making plans or technical decisions for the next iteration; this would be done in the iteration planning meeting at the start of the next iteration

Explanation / Rationale

a) Is not correct. Strong communication skills, active listening, and teamwork abilities enable a tester to interact effectively with all stakeholders, however a deep knowledge of a variety of computer games that allowed them to get on well with one developer is not an example of a generic skill useful to testers
b) Is correct. Domain knowledge that can be used to understand and communicate with end-users and business representatives is one of the generic skills required by testers. A tester with experience as a pilot would make them better able to appreciate the acceptance criteria for the helicopter control system
c) Is not correct. Although programming skills could be considered as technical knowledge which can increase efficiency when utilizing some test tools, it is unlikely that these skills would improve their communication with business analysts
d) Is not correct. Although thoroughness, attention to detail, curiosity, and a methodical approach to identifying hard-to-find defects are all useful generic skills for testers, it is doubtful they would be generating test cases prior to starting exploratory testing. This is because one of the main tenets of exploratory testing is that the test cases are generated during the testing, not scripted in advance

Explanation / Rationale

a) Is correct. Value “1” covers “length incorrect” and covers “number of different digits incorrect”, however the system would not validate against this partition when hitting the first incorrect partition. Value “1111” covers “length correct” and “number of different digits incorrect. Value “1234” again covers “length correct” and also “number of different digits correct”
b) Is not correct. These three values achieve full coverage of the equivalence partitions, but full coverage can be achieved with two values
c) Is not correct. These two values only cover “number of different digits
d) Is not correct. These two values does not cover “number of different digits incorrect” equivalence partition

Explanation / Rationale

a) Is not correct. It is more often used in behavior-driven development (BDD)
b) Is not correct. It is the description of test-driven development (TDD)
c) Is correct. In acceptance test-driven development (ATDD) tests are written from acceptance criteria as part of the design process
d) Is not correct. It is used in BDD

Explanation / Rationale

a) Is not correct. Component Test-Driven Development is not a correct example of a test-first approach to development
b) Is not correct. Integration Test-Driven Development is not a correct example of a test-first approach to development
c) Is not correct. System Test-Driven Development is not a correct example of a test-first approach to development
d) Is correct. Acceptance Test-Driven Development (ATDD) is a well-known example of a test-first approach to development

Explanation / Rationale

a) Is not correct. Testers should review work products as soon as drafts are available to enable early testing as part of a shift-left approach. If they waited until the next development phase, then unnecessary development (and test) work could be started on unreviewed, flawed work products
b) Is correct. Testers should review work products as soon as drafts are available to enable early testing as part of a shift-left approach
c) Is not correct. Testers typically review work products that form the test basis as part of test analysis, not before test analysis and design
d) Is not correct. Testers should review work products as soon as drafts are available to enable early testing as part of a shift-left approach. Waiting until they are published means that any defects that could be found by tester review will be in the published document

Explanation / Rationale

a) Is correct. It is important that testers are involved from the beginning of the software development lifecycle (SDLC). It will increase understanding of design decisions and will detect defects early.
b) Is not correct. Both developers and testers will have more understanding of each other's work products and how to test the code
c) Is not correct. End users will not help the testers in increasing the quality of defect reports; also, users usually do not participate in low-level testing levels like integration testing
d) Is not correct. Being certified does not automatically mean that the tester will be better in test design

Explanation / Rationale

a) Is not correct. Retrospectives are more useful for identifying improvement opportunities and have little importance for clients
b) Is not correct. Business representatives are not giving feedback about the product itself. Therefore, there is no financial gain to the organization
c) Is correct. Regularly conducted retrospectives, when appropriate follow up activities occur, are critical to continual improvement of development and testing
d) Is not correct. Courage and respect are values of Extreme Programming and are not closely related to retrospectives

Explanation / Rationale

Error guessing is about anticipating the errors, defects and failures based on the tester’s knowledge.
a) Is not correct. This is an example of anticipating the developer’s error
b) Is not correct. This is an example of anticipating the defect
c) Is correct. This is an example of a potential root cause of a defect, which is neither an error, defect nor failure, and difficult for the tester to anticipate
d) Is not correct. This is an example of anticipating a failure, perhaps based on experience of previous systems in this application domain

Explanation / Rationale

a) Is correct. Performing only black-box testing does not provide a measure of actual code coverage. White-box coverage measures provide an objective measurement of coverage and provide the necessary information to allow additional tests to be generated to increase this coverage, and subsequently increase confidence in the code
b) Is not correct. This statement is correct, but it has nothing to do with black-box testing
c) Is not correct. In general there are no subsumes relationships between white-box and black-box techniques
d) Is not correct. White-box techniques are used to design tests based on the test object itself, while black-box techniques are used to design tests based on the specification. Therefore, there is no relation between coverage items derived from these two types of techniques

Explanation / Rationale

The average development effort is $900,000 and the average test effort is $90,000 (calculated from the four projects).
The average test-to-development effort ratio is 1:10 ($90,000 : $900,000), which means that historically, on average, the test effort is 10% of the development effort.
So if the development effort is estimated to be $800,000, the estimated test effort is estimated as:

10% * $800,000 = 0.1 * $800,000 = $80,000.

Thus:
a) Is not correct
b) Is correct
c) Is not correct
d) Is not correct

Explanation / Rationale

a) Is not correct
b) Is not correct
c) Is not correct
d) Is correct. This rule holds for all SDLC models

Explanation / Rationale

a) Is not correct. In the whole-team approach, testers play a vital role by sharing their testing expertise with the team and guiding product development. They collaborate with other team members to achieve the desired quality levels and work with business representatives to create acceptance tests. Testers also partner with developers to determine the optimal test strategy and automation approaches
b) Is correct. By leveraging the diverse skill sets of each team member most effectively, the whole-team approach fosters superior team dynamics, promotes robust communication and collaboration, and generates a synergistic effect that benefits the entire project
c) Is not correct. The whole-team approach allows any team member with the requisite skills and knowledge to undertake any task, thus specialist team members are not an advantage of this approach
d) Is not correct. There is no specific guidance on the optimum size of teams using the whole-team approach, and there is no suggestion that larger teams are better

Explanation / Rationale

a) Is not correct. The fundamental strength of white-box test techniques is that the entire software implementation is taken into account during testing
b) Is not correct. White-box coverage measures provide an objective measure of coverage and provide the necessary information to allow additional tests to be generated to increase this coverage
c) Is not correct. White-box test techniques can be used to perform reviews (static testing)
d) Is correct. This is the weakness of the white-box test techniques. They are not able to identify the missing implementation, because they are based solely on the test object structure, not on the requirements specification

Explanation / Rationale

a) Is not correct. The expected result is “the application should accept the provided input and create the user”. The actual result is “The application hangs up after entering “Test input. $ä””.
b) Is not correct. There is a reference to the test case and to the related requirement and it states that the defect is rejected. Also, the defect status would not be very helpful for the developers
c) Is correct. We do not know in which test environment the anomaly was detected, and we also do not know which application (and its version) is affected
d) Is not correct. The defect report states that the anomaly is urgent, that it is a global issue (i.e., many, if not all, test administration accounts are affected) and states the impact is high for business stakeholders

Explanation / Rationale

Considering each of the listed task descriptions:

1. The quality characteristics to be evaluated and the exit criteria are selected - (Planning (C): Defining the review scope, purpose, work product to be reviewed, quality characteristics to be evaluated, areas of focus, exit criteria, supporting information such as standards, effort, and timeframes.)
2. Everyone has access to the work product - (Review initiation (B): Ensuring all participants have access to the work product and necessary resources, and clarifying their roles and responsibilities.)
3. Anomalies are identified in the work product - (Individual review (A): Evaluating the work product's quality, identifying and logging anomalies, recommendations, and questions using review techniques like checklist-based and scenario-based reviewing.)
4. Anomalies are analyzed and discussed - (Communication and analysis (D): Analyzing and discussing each anomaly, determining its status, ownership, and required actions, and making review decisions, normally in a meeting. This could include determining the need for a follow-up review.)

Thus:
a) Is not correct
b) Is not correct
c) Is not correct
d) Is correct. The correct match is: 1C, 2B, 3A, 4D

Explanation / Rationale

a) Is not correct. Test progress reports are mostly used during test monitoring and control, and test completion, not during test design
b) Is correct. A test completion report is prepared during test completion, when a project, test level, or test type is complete and when, ideally, its exit criteria have been met. This report uses information from test progress reports and other data
c) Is not correct. Test progress reports are mostly used during test monitoring and control, and test completion, not during test analysis
d) Is not correct. Test progress reports are most used during test monitoring and control, and test completion, not during test planning

Explanation / Rationale

a) Is not correct. Test monitoring involves the ongoing checking of all activities and comparison of actual progress against the test plan. Test control involves taking the actions necessary to meet the test objectives of the test plan. No test data are prepared during these activities
b) Is not correct. Test analysis includes analyzing the test basis to identify test conditions and prioritize them. Test design includes elaborating the test conditions into test cases and other testware. Test data are not prepared during these activities
c) Is correct. Test implementation includes creating or acquiring the testware necessary for test execution (e.g., test data)
d) Is not correct. Test completion activities occur at project milestones (e.g., release, end of iteration, test level completion), so it is too late for preparing test data

Explanation / Rationale

a) Is not correct. Risk management consists of risk analysis and risk control. Neither of these activities supports the reassembly of the files that made up the release, because these activities deal with risks, not with configuration items
b) Is not correct. Test monitoring is concerned with gathering information about testing. This information is used to assess test progress and to measure whether the test exit criteria or the test tasks associated with the exit criteria are satisfied, such as meeting the targets for coverage of product risks, requirements, or other acceptance criteria. Test control uses the information from test monitoring to provide, in the form of control directives, guidance and the necessary corrective actions to achieve the most effective and efficient testing. None of these activities deal with the management of configuration items
c) Is not correct. The whole-team approach builds on the tester’s skill to work effectively in a team context and to contribute positively to the team goals. So, it focuses on team-related issues, not on configuration items
d) Is correct. Configuration management provides a discipline for identifying, controlling, and tracking work products. Configuration management keeps a record of changed configuration items when a new baseline is created. Using configuration management, it is possible to revert to a previous baseline in order to reproduce previous test results

Explanation / Rationale

The ‘absence-of-defects fallacy’ is concerned with the idea that ensuring correctness in accordance with the requirements (i.e., verifying the absence of implementation defects) does not guarantee user satisfaction with the system. To address this it is also necessary to validate that the system meets users' needs and expectations, fulfills business objectives, and outperforms competing systems.
a) Is not correct. The ‘testing shows the presence, not the absence of defects’ principle explains that while testing can detect the existence of defects in the test object, it is not possible to demonstrate that there are no defects and, therefore, guarantee its correctness. Therefore, explaining that it is not possible for testing to show the absence of defects would partially address this principle, not the ‘absence-of-defects’ fallacy
b) Is correct. By supporting the end user to perform acceptance testing it should be possible to validate that the system meets users' needs and expectations
c) Is not correct. It is not possible to ensure that no implementation defects remain in the delivered system as the ‘testing shows the presence, not the absence of defects’ principle explains that while testing can detect the existence of defects in the test object, it is not possible to demonstrate that there are no defects and, therefore, guarantee its correctness
d) Is not correct. Modifying tests that cause no failures to ensure few defects remain is one way to address the ‘tests wear out’ principle. This principle is concerned with the idea that repeating identical tests on unaltered code is unlikely to uncover novel defects and therefore, modifying tests may be essential. This will not validate that the system meets users' needs and expectations

Explanation / Rationale

a) Is not correct. The whole-team approach allows any team member with the requisite skills and knowledge to undertake any task, however that does not mean that team members can take on any role at any time. Typically, they only take on roles in which they are competent, and there is no suggestion that every team member can do every role
b) Is not correct. The whole-team approach applies to how a single team (typically in Agile software development) works; it does not cover how multiple teams are supposed to work on larger projects, and it does not suggest that only one ‘whole’ team is needed for a complete project
c) Is not correct. The whole-team approach does not expect every team member to be involved in every important decision. For instance, there is no need for the business representative (i.e. the Product Owner) to be involved in every technical decision that does not affect the business outcome and implementing such an approach would unnecessarily slow down the team’s progress
d) Is correct. By leveraging the diverse skill sets of each team member most effectively, the whole-team approach fosters superior team dynamics, promotes robust communication and collaboration, and generates a team synergy that benefits the entire project

Explanation / Rationale

a) Is correct. This principle means that if the same tests are repeated over and over again, eventually these tests no longer find any new defects. This is probably why the tests all passed in this release as well
b) Is not correct. This principle says about the mistaken belief that just finding and fixing a large number of defects will ensure the success of a system
c) Is not correct. This principle says that a small number of components usually contain most of the defects
d) Is not correct. This principle states that testing all combinations of inputs and preconditions is not feasible

Explanation / Rationale

Considering each of the listed risks and their mitigations:

1. Long system responses (1) can be tested in performance testing (B)
2. Changes of consumers’ preferences (2) are usually out of our control, so usually we accept this risk (A)
3. Flooding of the server room (3) can cause significant loss, so we should transfer the risk, e.g., by buying an insurance policy (D)
4. That patients above a certain age receive inaccurate reports (4) suggests a potential boundary problem, which can be effectively detected with techniques like BVA (C)

Thus:
a) Is not correct
b) Is not correct
c) Is correct. The correct combinations of risk and mitigation are: 1B, 2A, 3D and 4C
d) Is not correct

Explanation / Rationale

a) Is not correct. A lack of usability provided through the user interface can be detected through a review using a suitable checklist, but the lack of usability can also be identified by getting several typical users to dynamically test the user interface and provide feedback on its usability
b) Is correct. A code review can detect code that cannot be reached by any path, however dynamic tests can only exercise reachable code and cannot determine that code cannot be reached without running every possible combination of inputs and input states, which is impractical for real code
c) Is not correct. Poor response times for most of the expected users are difficult to determine without executing the code (i.e., by static testing), so in this situation dynamic testing could find a defect, but static testing is unlikely to find it
d) Is not correct. A review of the code by someone who is aware of the required features could detect that the required features had not been implemented in the code, and dynamic testing could also be used to determine that these required features had not been implemented

Explanation / Rationale

a) Is not correct. A line with a defect, when executed, does not have to cause a failure. For example, a line x := y / z will cause a failure only when z equals 0
b) Is not correct. 100% statement coverage does not guarantee 100% branch coverage. For example, a test case with x=0 for the code

1. IF (x=0) THEN
2. A;
3. ENDIF

achieves 100% statement coverage but does not cover the branch from 1 to 3
c) Is correct. 100% statement coverage means that each executable statement was executed at least once
d) Is not correct. The removed test case may provide coverage of some statements that are not covered by either of the other two test cases, in which case the remaining two test cases together will not achieve 100% statement coverage

Explanation / Rationale

a) Is correct. The primary benefit of independence in testing is that testers are more likely to identify different types of failures and defects compared to developers, due to their varied backgrounds, technical viewpoints, and potential biases, including cognitive bias. However, the main disadvantage of independence in testing is that testers may become isolated from the development team, leading to communication problems, a lack of collaboration, and potentially an adversarial relationship, with testers being blamed for delays and bottlenecks in the release process
b) Is not correct. A developer’s familiarity with the code does not mean that they rarely find defects in it, instead this familiarity means they can efficiently find many defects in their own code. And, rather than developers and testers having a shared background, developers having a different background to testers is normally cited as the reason that testers and developers find different kinds of defects
c) Is not correct. Testing can be conducted at different levels of independence, ranging from no independence for the author to very high independence for testers from outside the organization. In most projects, multiple levels of independence are utilized, with developers performing component and component integration testing, the test team performing system and system integration testing, and business representatives performing acceptance testing. So, testers can be in the developer’s team and do not need to come from outside the organization. Knowledge of the application domain will change from case-to-case and is not dependent on the level of independence
d) Is not correct. Testing can be conducted at different levels of independence, ranging from no independence for the author to very high independence for testers from outside the organization, with testers from outside the developer’s team generally more independent than testers from within the team. However, there is more reason to believe that testers from outside the team are likely to be more isolated from the developers and so are more likely to be blamed for delays in product release

Explanation / Rationale

Because TC1 and TC3 failed in Execution 1 (i.e., test (1) and test (3)), test (4) and test (6) are confirmation tests.
Because TC2 and TC3 failed in Execution 2 (i.e., tests (5) and (6)), test (8) and test (9) are also confirmation tests.
TC2 passed in Execution 1 (i.e., test (2)), so test (5) is a regression test.
TC1 passed in the Execution 2 (i.e., test (4)), so test (7) is also a regression test.
Thus:
a) Is not correct
b) Is correct
c) Is not correct
d) Is not correct

Explanation / Rationale

a) Is not correct. Dynamic testing does cause failures (from which defects can then be located and fixed). However, debugging is concerned with locating defects and fixing these defects. Therefore, debugging does not fix failures
b) Is not correct. Both testing and debugging contribute to improving the quality of the test object, so should really both be considered positively. Debugging is generally considered to be a positive activity as it is fixing something. Dynamic testing does involve intentionally causing the test object to fail, which is why some people consider it a negative activity, but that is a very narrow view (and not one typically held by testers). Both positive and negative test cases are possible. Positive test cases check that the test object correctly performs what it is supposed to do, while negative testing checks that the test object does not do what it is not supposed to do
c) Is correct. Testing determines that defects exist either directly through observation of the defect in reviews (or by a tool in static analysis), or indirectly by causing a failure in dynamic testing. Debugging is a separate activity from testing (normally performed by developers) and is concerned with locating defects (only for dynamic testing) and fixing the defects
d) Is not correct. The causes of defects are typically human errors. Testing finds defects either directly through static testing, or indirectly by causing failures in dynamic testing, and debugging fixes defects. So, testing does not find the cause of defects and debugging does not fix the causes of defects

Explanation / Rationale

a) Is correct. The client is in a different location and time zone, so it may be difficult to communicate face-to-face
b) Is not correct. Dashboards are usually available to any user at any time, so the difference in time zones will not be as much of a hindrance to communication as verbal, face-to-face communication
c) Is not correct. Although the time difference between Europe and America is several hours, and this may cause some inconvenience, it's certainly not as great as with communicating face-to-face
d) Is not correct. Video conferencing tools are a convenient means of communication. Although communication between Europe and America during working hours usually requires one party to connect in the very early or very late hours, this is not as much of an inconvenience as verbal, face-to-face communication

Explanation / Rationale

Considering each of the listed test activities and their output testware:

A. Test analysis - prioritized test conditions (4) (e.g., acceptance criteria), and defect reports for defects identified in the test basis
B. Test design - prioritized test cases, test charters, coverage items (1), test data requirements, and test environment requirements
C. Test implementation - test procedures, automated test scripts, test suites, test data, test execution schedule (3), and test environment elements such as stubs, drivers, simulators, and service virtualizations
D. Test completion - test completion report, documented lessons learned, action items for improvement, and change requests (2) (as product backlog items)

Thus:
a) Is correct. The correct match is: 1B, 2D, 3C, 4A
b) Is not correct
c) Is not correct
d) Is not correct

Explanation / Rationale

a) Is not correct. Validating that documented requirements are met is incorrect as validation is concerned with meeting user requirements and expectations, while verification is concerned with meeting specified requirements, so this would be correct if we replaced ‘validating’ with ‘verifying’
b) Is correct. Causing failures and identifying defects is probably the most common objective of dynamic testing
c) Is not correct. Initiating errors and identifying root causes is incorrect because testers do not initiate errors, they try to cause failures. Errors are typically made by developers (and cannot really be initiated) and result in defects, which testers attempt to identify either directly through static testing or indirectly through failures with dynamic testing. Identifying root causes is useful but is part of debugging, which is a separate activity to testing
d) Is not correct. Verifying the test object meets user expectations is incorrect as verification is concerned with checking specified (documented) requirements are met, while validation is concerned with meeting user requirements and expectations, so this would be correct if we replaced ‘verifying’ with ‘validating’

Explanation / Rationale

a) Is correct. Checking that the sort function puts the elements of the list or array in ascending order is evaluating the functional correctness of the sort function, which is part of functional testing
b) Is not correct. Assessing whether the sort function meets its non-functional requirement to complete within one second is part of testing its performance efficiency, which is part of non-functional testing
c) Is not correct. Evaluating the ease with which the sort function can be modified from sorting ascending to sorting descending is testing its modifiability, a form of non-functional maintainability testing, which is part of non-functional testing
d) Is not correct. Assessing that the sort function still functions correctly when moved from a 32-bit to a 64-bit architecture is testing its adaptability, a form of portability testing, which is part of non-functional testing