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 not correct. The test case is related to viewing previous orders in the order history
b) Is not correct. The test case is related to viewing previous orders
c) Is not correct. The test case is related to viewing previous orders in the order history
d) Is correct. The test case is related to the registration process, which is not discussed in the user story. The user story is about viewing previous orders

Explanation / Rationale

a) Is not correct. The miscalculation of bonuses is a failure by the system, not a defect
b) Is not correct. The system not suitably supporting disabled users is a failure which eventually results in a fine, but the fine itself is not a failure (it appears to be the correct functioning of the regulatory system)
c) Is correct. The error is made by the programmer and this mistake is caused by them working under severe time pressure, which is the root cause of the subsequent defect
d) Is not correct. The poor design of the user interface, which does not suitably address disabled users, is a design defect caused by the designer error. Thus the design of the user interface includes a design defect not a designer error

Explanation / Rationale

Considering each of the listed test activities and their tasks:

A. 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. During this test analysis, defects in the test basis are typically uncovered, and the test object's testability may also be assessed. (Task 4)
B. Test design - Involves using test conditions to create test cases and other necessary testware, such as test data requirements and test charters for exploratory testing. (Task 1)
C. Test implementation - Test procedures, such as manual and automated test scripts, are created from test cases and may be assembled into test suites. Test procedures are prioritized and arranged in a test execution schedule. (Task 3)
D. Test completion - Occurs at project milestones, such as release, end of iteration or end of test level. Testware is identified and archived or handed to the appropriate teams for reuse, the test environment is shut down, and the test activities are analyzed for lessons learned and future improvements. (Task 2)

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

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

Considering each of the listed testware, and the test activity that produces it:

i. The test completion report is an output of the test completion activity
ii. Data held in a database used for test inputs and expected results is the test data - output of test implementation activity
iii. The list of elements needed to build the test environment is the test environment requirements - output of test design activity.
iv. Documented sequences of test cases in execution order are the test procedures - output of test implementation activity
v. Test cases - output of test design activity

Test implementation produces the following outputs: test procedures (iv), automated test scripts, test suites, test data (ii), test execution schedule, and test environment elements such as stubs, drivers, simulators, and service virtualizations.

Thus:
a) Is correct. Items ii and iv in the list are produced as a result of test implementation
b) Is not correct
c) Is not correct
d) Is not correct

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

a) Is not correct. The organization’s marketing team is unlikely to perform much testing (although in some organizations they may be involved with acceptance testing), so their average level of experience (most of which would be in marketing) is not likely to impact how testing is performed for a given test object
b) Is not correct. The level of knowledge of users that a new system is being built for them is unlikely to affect how testing is performed. Any user involvement that could affect how testing is performed is more likely to be as a result of decisions made by the testers, customer and project manager
c) Is correct. The number of years’ experience of the members of the performance testing team will help to determine the capabilities and knowledge (e.g., of different tools and defect types) that the team members will apply when they are testing
d) Is not correct. The organizational structure of the different end users (who may be varied) will change between users. So, it may not even be known when the application is being tested, and the end user’s organizational structure can thus have little effect on how the testing is performed

Explanation / Rationale

a) Is not correct. To ensure successful reviews, it's important to secure management's support for the review process, however that does not mean that they should participate as reviewers
b) Is correct. To ensure successful reviews, it's important to break the work product into parts that are small enough to be reviewed in a reasonable timescale to prevent reviewers from losing focus during individual review or review meetings
c) Is not correct. To ensure successful reviews, it's important to clearly define objectives and measurable exit criteria, without evaluating participants
d) Is not correct. To ensure successful reviews, it's important to break down the review into smaller chunks to prevent reviewers from losing focus during individual review or review meetings. So you should not plan to cover one document per review

Explanation / Rationale

a) Is not correct. DevOps enhances testing in several ways, such as by providing fast feedback on code quality, automated regression testing that minimizes regression risk, and promoting a shift-left approach with high-quality code submission and component tests. This is largely provided through continuous integration, where the developers submit component (unit) tests with their new code, which must pass for the code to be admitted to the build. Therefore, developers do need to complete component testin
b) Is correct. DevOps enhances testing in several ways, such as by providing fast feedback on code quality, automated regression testing that minimizes regression risk, and promoting a shift-left approach with high-quality code submission and component tests
c) Is not correct. DevOps enhances testing in several ways, such as by providing fast feedback on code quality, automated regression testing that minimizes regression risk, and promoting a shift-left approach with high-quality code submission and component tests. Testers do not attempt to treat developers and operations equally by spending more time on release testing, although a shift-right approach to testing (testing in production) may well be used
d) Is not correct. Automated processes like continuous integration/continuous delivery (CI/CD) in DevOps facilitate stable test environments and reduce the need for manual testing, however, there is a risk of overlooking the importance of manual testing, especially from a user's perspective

Explanation / Rationale

a) Is not correct. Adequate time for individuals is a success factor
b) Is not correct. Splitting work products into small adequate parts is a success factor
c) Is not correct. Avoiding behaviors that might indicate boredom, exasperation, etc. is a success factor
d) Is correct. During reviews one can find defects, not failures

Explanation / Rationale

i. Is true. Having domain knowledge is an important tester skill
ii. Is false. This is a task of the business analyst together with the business representative
iii. Is true. Being a good team player is an important skill
iv. Is false. Planning and organizing the work of the team is a task of the test manager or, mostly in an Agile software development project, the whole team and not just the tester
v. Is true. Critical thinking is one of the most important skills of testers

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

Explanation / Rationale

a) Is not correct. In exploratory testing, test cases are usually created during the exploratory testing session, alongside test analysis, test implementation and test execution
b) Is not correct. In exploratory testing, tests are simultaneously designed, executed, and evaluated while the tester learns about the test object
c) Is not correct. Exploratory testing results depend heavily on the tester’s experience, so even if the results of exploratory testing can be used as a predictor of risk and used to assess whether there will be fewer or more defects, for example, compared to the previous exploratory testing session, they are not a good example of reliable defect prediction models that can predict the number of remaining defects
d) Is correct. During exploratory testing, the testers can use any techniques that they find useful

Explanation / Rationale

a) Is correct. Since 100% statement coverage is achieved, every statement, including the ones with defects, must have been executed and evaluated at least once
b) Is not correct. Coverage depends on what is tested, not on the number of test cases. For example, for code “if (x==0) y=1”, one test case (x=0) achieves 100% statement coverage, but two test cases (x=1) and (x=2) together achieve only 50% statement coverage
c) Is not correct. If there is a loop in the code there may be an infinite number of possible paths, so it is not possible to execute all the possible paths in the code
d) Is not correct. Exhaustive testing is not possible (see the seven testing principles section in the syllabus). For example, for code “input x; print x” any single test with arbitrary x achieves 100% statement coverage, but covers one input value

Explanation / Rationale

a) Is not correct. The test pyramid emphasizes having a larger number of tests at the lower test levels
b) Is correct. It is not true that near the top of pyramid, test automation should be more formal
c) Is not correct. Usually component testing and component integration testing are automated using API-based tools
d) Is not correct. For system testing and acceptance testing, the automated tests are typically created using GUI-based tools

Explanation / Rationale

a) Is not correct. In agile software development, deliverables are produced in each iteration, and the frequent delivery of increments necessitates extensive regression testing. Although some (or all) of this regression testing may be automated, the regression testing (automated or not) cannot be replaced by system test automation
b) Is correct. If a sequential development model is used, then early in the lifecycle no code is available for execution, and so during this time static testing (e.g., reviews) is performed. Later in the lifecycle, when code is available for execution, dynamic testing is possible. Note, however, that preparation for dynamic testing will often occur early in any software development lifecycle
c) Is not correct. If an iterative development model, like agile software development, is used, then component tests may well be used for regression testing for each iteration. In which case, there is a strong argument for automating these component tests, which will have to be run frequently, and there is unlikely to be a strong argument for developers performing these component tests manually
d) Is not correct. In most incremental development models, deliverables are produced in each increment, requiring both static and dynamic testing at all test levels for each increment delivered

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

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. Priorities for user stories are determined by the business representative together with the development team
b) Is not correct. Testers focus on both functional and non-functional aspects of the system to be tested
c) Is correct. According to the syllabus, this is one of the ways testers add value to iteration and release planning
d) Is not correct. Early test design is not part of release planning. Early test design does not automatically guarantee the release of quality software

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

a) Is not correct. The testing role is primarily responsible for the technical and engineering aspects of testing, such as test analysis, test design, test implementation, and test execution. Evaluating the test basis for defects and the test object for testability are tasks performed as part of test analysis, so it is likely they are tasks performed by the testing role
b) Is not correct. The testing role is primarily responsible for the technical and engineering aspects of testing, such as test analysis, test design, test implementation, and test execution. Defining the test environment requirements is a task performed as part of test design, so it is likely to be a task performed by the testing role
c) Is not correct. The testing role is primarily responsible for the technical and engineering aspects of testing, such as test analysis, test design, test implementation, and test execution. Assessing the testability of a test object is a task performed as part of test analysis, so it is likely to be a task performed by the testing role
d) Is correct. The test management role primarily involves activities related to test planning, test monitoring and control, and test completion. Thus, creating the test completion report, which is the prime output from the test completion activity, is likely to be a task performed by the test management role

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

The domain for the password length has three equivalence partitions:

• passwords too short {0, 1, …, 4, 5}
• passwords OK {6, 7, …, 11, 12}
• passwords too long {13, 14, …}

To achieve full coverage for 3-value BVA we need to test the following values:

0, 1, 4, 5, 6, 7, 11, 12, 13, 14.

Since 2-value BVA is already covered, this means that we have already tested the passwords of length:

0, 5, 6, 12 and 13.

This means that the additional lengths that need to be covered to move from 2-value to 3-value are:

1, 4, 7, 11 and 14.

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

Explanation / Rationale

a) Is not correct. This should be a team activity and not overruled by one team member
b) Is correct. If test estimates are not the same, but the variation in the results is small, applying rules like “accept the number with the most votes” can be applied
c) Is not correct. There is no consensus yet as some say 13, others say 8
d) Is not correct. A feature should not be removed only because the team cannot agree on the test estimates

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. 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. This is an example of a risk monitoring activity, not risk analysis
b) Is not correct. This is an example of an architectural decision, not related with testing
c) Is not correct. This is an example of performing a quantitative risk analysis and is not related to thoroughness or scope of testing
d) Is correct. This shows how risk analysis impacts the thoroughness of testing (i.e., the level of detail)

Explanation / Rationale

Test cases TC1, TC2, TC3 and TC4 cover, respectively, rules R2, R3, R7 and R6 in the decision table.
a) Is correct. The conditions “66-year-old”, “unregistered” and “no experience” match rule R4, which is not covered by the existing test cases, so after adding this test case, the decision table coverage will increase
b) Is not correct. The conditions “55-year-old”, “unregistered” and “2 years of experience” match rule R2, already covered by TC1. So adding this test case will not increase the coverage
c) Is not correct. The conditions “19-year-old”, “registered” and “5 years of experience” match rule R6, already covered by TC4. So adding this test case will not increase the coverage
d) Is not correct. The existing test cases cover only 4 out of 7 columns of the decision table. The coverage can be increased by adding test cases that cover yet uncovered columns, that is, R1, R4 and R5

Explanation / Rationale

a) Is correct. Test design involves using test conditions to create test cases and other necessary testware, such as test data requirements and test charters for exploratory testing. Test environment requirements are also specified, including the necessary infrastructure and tools
b) Is not correct. Test execution involves executing test cases (as part of test procedures), however it does not directly cover the other testware mentioned in the question, such as test data requirements, test environment requirements and test conditions
c) Is not correct. Test analysis is used 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. While this activity involves working with test conditions, it does not cover the other testware mentioned in the question, such as test data requirements, test environment requirements and test cases
d) Is not correct. Test implementation includes the generation of test procedures, such as manual and automated test scripts, which are created from test cases and may be assembled into test suites. Test procedures are prioritized and arranged in a test execution schedule. Test data is created, and the test environment built, and its set up verified. While this activity involves explicitly working with test cases, and may use test data requirements and test environment requirements to create test data and the test environment, it does not cover test conditions

Explanation / Rationale

a) Is correct. Each test level has specific and distinct test objectives as a different form of test object (e.g., single component, complete system) is tested at each test level and overlapping test objectives would lead to unnecessary duplication
b) Is not correct. Test analysis and design for a given test level should start during the corresponding development phase to facilitate early testing (e.g., acceptance test analysis and design should begin during requirements analysis). Test implementation will generally start later, and test execution will start during the test level
c) Is not correct. Test design for a given test level should start during the corresponding development phase to facilitate early testing, however test design (e.g., test case generation) needs to be based on an agreed test basis, not an early draft, otherwise significant test effort may be wasted on creating test cases for a design that later changes
d) Is not correct. Quality control applies to all development activities, meaning that every software development activity has a corresponding test activity. However, the same symmetry does not apply to dynamic and static testing. There are some static testing activities (e.g., static analysis) for which there is no obvious corresponding dynamic testing activity

Explanation / Rationale

“Small garden” and “large garden” can go only with “ground floor”, so we need two test cases with “ground floor” which cover these two “garden type” partitions.
We need two more test cases to cover the two other “floor” partitions and a remaining ”garden type” partition of “no garden”.
We need a total of four test cases:

TC1 (ground floor, small garden)
TC2 (ground floor, large garden)
TC3 (first floor, no garden)
TC4 (second or higher floor, no garden)

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

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. When a system is retired, this can require testing of data migration, which is a form of maintenance testing
b) Is not correct. Regression testing verifies whether a fix accidentally affected the behavior of other parts of the code, but now we are talking about data migration to a new system
c) Is not correct. Component testing focuses on individual hardware or software components, not on data migration
d) Is not correct. Integration testing focuses on interactions between components and/or systems, not on data migration

Explanation / Rationale

a) Is not correct. Decision table testing is a black-box test technique, so it is specification-based, not structure-based – the test cases are not based on the decisions in the source code. In branch testing, the test cases are derived from knowledge of the control flow of the test object
b) Is not correct. Anticipation of potential defects is used in error guessing (an experience-based test technique), not in branch testing (a structure-based technique). In decision table testing, the test cases are derived from the specification that describes the business logic
c) Is not correct. If a test case is based on the knowledge of the control flow of the test object, it is a white-box test technique. Decision table testing is typically based on an analysis of business logic, so it is a black-box test technique. In branch testing, test cases are not derived from the specification – this would make it a black-box test technique. Branch testing is a white-box test technique, where test cases are derived based on the source code structure
d) Is correct. Decision table testing is a black-box test technique, so it is based on an analysis of the specified behavior of the test object without reference to its internal structure. Therefore, the test cases are independent of how the software is implemented. Branch testing is a white-box test technique, so test cases are based on an analysis of the test object’s internal structure and processing. As the test cases are dependent on how the software is designed and coded, they can only be created after the design or implementation of the test object

Explanation / Rationale

a) Is not correct. Assuming that testers could check the ease of changing the currency exchange system then it would be done by maintainability testing rather than maintenance testing, so this is not a trigger for maintenance testing
b) Is correct. A system modification (such as a fix or enhancement) is an example of a trigger for maintenance testing. The removal of the refund option of the currency exchange system was a fix that would lead to maintenance testing
c) Is not correct. If the agile team has started developing a user story that adds a new customer loyalty feature to the currency exchange system, then this will result in them testing the new feature, and then they would perform regression testing. No maintenance testing is required in this situation
d) Is not correct. Reconfiguration of the currency exchange system to support both the local language and English currency transactions is not a system modification, a change to the operational environment, or a system retirement, which are the three triggers for maintenance testing

Explanation / Rationale

a) Is not correct. The feedback is from stakeholders (e.g., business representative, end user), not from developers, so this feedback is not likely to inform managers which developers are more or less productive
b) Is not correct. Early and frequent feedback from stakeholders is not used by project managers to prioritize how they interact with the different stakeholders
c) Is correct. Obtaining feedback from stakeholders early and often in the software development process can be highly beneficial as it facilitates early communication of potential quality issues, can prevent misunderstandings about requirements, and ensures that any changes in stakeholder requirements are understood and implemented sooner
d) Is not correct. Early and frequent feedback can prevent the development of a product that does not meet stakeholder needs, and results in costly rework and missed deadlines, so, ideally there should be no delay. Also, the feedback is from stakeholders (not to them), which includes the end users, so the end users providing feedback will not aid the end users’ understanding

Explanation / Rationale

There are five columns in the decision table. Each test case covers one of them.

TC1 and TC2 both cover Rule 4
TC3 and TC4 both cover Rule 2
TC5 covers Rule 5

So, these five test cases cover three out of five columns, achieving a coverage of (3/5)*100% = 60%. Therefore, option b) is the CORRECT option.
Thus:
a) Is not correct
b) Is correct
c) Is not correct
d) Is not correct

Explanation / Rationale

a) Is not correct. Although it is correct to say that in Agile software development, some of the test management tasks may be handled by the Agile team itself, the testing role is not primarily the responsibility of a single individual from outside the team. Instead the testing is more likely to be performed by various team members following the whole-team approach
b) Is not correct. The test management role primarily involves activities related to test planning, test monitoring and control, and test completion. So, although this statement is partially correct, it is wrong to say that the testing role is primarily responsible for test monitoring and control
c) Is correct. In Agile software development, some of the test management tasks may be handled by the Agile team itself. However, for test activities that span multiple teams within an organization, test managers outside of the development team may perform these tasks
d) Is not correct. The test management role primarily involves activities related to test planning, test monitoring and control, and test completion, while the testing role is primarily responsible for the technical and engineering aspects of testing, such as test analysis, test design, test implementation, and test execution. Thus the test management role is not normally responsible for test analysis and test design, although it is correct to say that the testing role is primarily responsible for test implementation and execution

Explanation / Rationale

The equivalence partitions are: {…, 99, 100}, {101, 102, …, 198, 199}, {200, 201, …}.
Thus, there are 4 boundary values, which are: 100, 101, 199 and 200.
In 2-value BVA, for each boundary value there are two coverage items (the boundary value and its closest neighbor belonging to the adjacent partition). As the closest neighbors are also boundary values in the adjacent partition, then there are just four coverage items.

Thus:
a) Is not correct. Only 100 and 200 are valid coverage items for 2-value BVA, so we achieve 50% coverage
b) Is not correct. Only 100 and 200 are valid coverage items for 2-value BVA, so we achieve 50% coverage
c) Is not correct. Only 100 and 101 are valid coverage items for 2-value BVA, so we achieve 50% coverage
d) Is correct. 101, 199 and 200 are valid coverage items for 2-value BVA, so we achieve 75% coverage

Explanation / Rationale

a) Is not correct. While the sentence is true, it does not provide much value for the developer
b) Is correct. From the test results it seems that the system ignores duplicates and sorts the list disregarding the repetitions. This is probably the cause of failures in TC3, TC4, TC5. Such information may help the developer to find the defect and fix it more efficiently
c) Is not correct. The system does not fail in sorting negative numbers. The problem is rather in disregarding duplicates
d) Is not correct. The test cases TC3, TC4 and TC5 fail, but we aren’t aware that the test cases have any defects