ISTQB Certified Tester Foundation Level v4.0 ISTQB-CTFL Exam Practice Test

Answer : D

Defect clustering is a testing principle that states that a small number of modules contain most of the defects detected during pre-release testing, or are responsible for most of the operational failures. Defect clustering can be explained by Pareto's principle (also known as the 80-20 rule), which states that approximately 80% of the problems are found in 20% of the modules. Defect clustering suggests a change to the current test strategy for the next test cycle, as it implies that more effort should be allocated to test the modules that have shown high defect density or criticality. Pesticide paradox is another testing principle that states that if the same tests are repeated over and over again, eventually they will no longer find any new defects. Pesticide paradox suggests a change to the current test strategy for the next test cycle, but not based on defect clustering, but rather on test diversity and coverage. Early testing is a testing principle that states that testing activities should start as early as possible in the software development life cycle and should be focused on defined objectives. Early testing does not suggest a change to the current test strategy for the next test cycle, but rather a proactive approach to prevent defects from occurring or propagating. Absence-of-errors fallacy is a testing principle that states that finding and fixing defects does not help if the system built is unusable and does not fulfill the users' needs and expectations. Absence-of-errors fallacy does not suggest a change to the current test strategy for the next test cycle, but rather a focus on quality attributes and user requirements. Verified Reference: A Study Guide to the ISTQB Foundation Level 2018 Syllabus - Springer, Chapter 1, page 9-10.

Answer : A

Static testing, such as code reviews and static analysis, is particularly effective at identifying issues related to code structure and modularization. These techniques allow for the inspection of the code without executing it, making it easier to spot problems related to how the code is organized. Dynamic testing, on the other hand, focuses on the execution of code and is better suited for identifying runtime issues but does not easily reveal structural problems. The ISTQB CTFL Syllabus v4.0 highlights the strengths of static testing in uncovering such structural issue

Answer : D

Exercising at least one of the decision outcomes for all decisions within the code, ensures achieving full branch coverage, which is a test coverage criterion that requires that all branches in the control flow of the code are executed at least once by the test cases. A branch is a basic block of code that has a single entry point and a single exit point, and a decision is a point in the code where the control flow can take more than one direction, such as an if-then-else statement, a switch-case statement, a loop statement, etc. The decision outcomes are the possible paths that can be taken from a decision, such as the then branch or the else branch, the case branch or the default branch, the loop body or the loop exit, etc. The other statements are false, because:

The minimum number of test cases needed to achieve full branch coverage, is usually higher than that needed to achieve full statement coverage, which is a test coverage criterion that requires that all executable statements in the code are executed at least once by the test cases. This is because branch coverage is a stronger criterion than statement coverage, as it implies statement coverage, but not vice versa. For example, a single test case can achieve full statement coverage for an if-then-else statement, but two test cases are needed to achieve full branch coverage, as both the then branch and the else branch need to be exercised.

If full branch coverage has been achieved, then all unconditional branches within the code have not necessarily been exercised, as unconditional branches are branches that do not depend on any decision, and are always executed, such as a goto statement, a break statement, a return statement, etc. Unconditional branches are not part of the branch coverage criterion, as they do not represent different paths in the control flow of the code. However, they are part of the statement coverage criterion, as they are executable statements in the code.

If full branch coverage has been achieved, then all combinations of conditions in a decision table have not necessarily been exercised, as a decision table is a test design technique that represents the logical relationships between multiple conditions and their corresponding actions, in a tabular format. A decision table can have more combinations of conditions than the number of decision outcomes in the code, as each condition can have two or more possible values, such as true or false, yes or no, etc. For example, a decision table with four conditions can have 16 combinations of conditions, but the corresponding code may have only two decision outcomes, such as pass or fail. To exercise all combinations of conditions in a decision table, a stronger test coverage criterion is needed, such as condition combination coverage, which requires that all possible combinations of condition outcomes in the code are executed at least once by the test cases. Reference: ISTQB Certified Tester Foundation Level (CTFL) v4.0 sources and documents:

ISTQB Certified Tester Foundation Level Syllabus v4.0, Chapter 2.3.1, Test Coverage Criteria Based on the Structure of the Software

ISTQB Glossary of Testing Terms v4.0, Branch Coverage, Statement Coverage, Branch, Decision, Decision Outcome, Unconditional Branch, Decision Table, Condition Combination Coverage

Answer : A

This question asks for a non-functional aspect of testing the download process of a mobile application. Option A, 'It was easy to locate, download and install the application,' refers to usability, which is a non-functional quality attribute. Non-functional testing involves testing the system's attributes, such as usability, performance, reliability, etc., rather than specific behaviors or functions. Options B, 'The application was correctly downloaded,' C, 'The application created an installation log file in a given folder,' and D, 'The application installed only after the user's approval,' describe functional aspects, focusing on what the software does rather than how it performs or is experienced by the user.

Answer : D

An incident is any event that occurs during testing that requires investigation. An incident management tool is a software tool that supports recording and tracking incidents throughout their life cycle. A QA manager of a start-up company needs to implement within a week a low cost incident management tool. The best option for this case is to manage the incidents in a spreadsheet posted on the intranet. This option has several advantages over other options:

It is low cost, as it does not require purchasing any additional software or hardware.

It is easy to implement within a week, as it does not require installing or configuring any complex software or hardware.

It is accessible and transparent, as it can be viewed and updated by anyone who has access to the intranet.

It is structured and organized, as it can store and display various information about incidents, such as identifier, summary, description, severity, priority, status, resolution, etc. The other options are not suitable for this case, as they have several disadvantages over the chosen option:

Documenting incidents on a large board in the lab is not a good option, as it is not accessible or transparent to anyone who is not physically present in the lab. It is also not structured or organized, as it may not store or display all the necessary information about incidents.

Purchasing and deploying an incident management tool is not a good option, as it is not low cost or easy to implement within a week. It may require spending a significant amount of money and time on acquiring, installing and configuring the software or hardware.

Managing the incidents through emails and phone calls is not a good option, as it is not structured or organized. It may lead to confusion, inconsistency or loss of information about incidents. Verified Reference: A Study Guide to the ISTQB Foundation Level 2018 Syllabus - Springer, Chapter 3, page 32-33.

Answer : B

To achieve the highest level of transition coverage, one must consider all the possible transitions between the states in the given state model of the sales order software. The transitions in the sequence provided in Option B - 'IN PRODUCTION -> SHIPPED -> INVOICED -> CANCELLED -> PLACED -> IN PRODUCTION' cover all the states and transitions effectively. This covers the transitions from IN PRODUCTION to SHIPPED, SHIPPED to INVOICED, INVOICED to CANCELLED, CANCELLED to PLACED, and PLACED to IN PRODUCTION, thereby maximizing the transition coverage.

ISTQB Certified Tester Foundation Level Syllabus v4.0, Section 4.3.5.

Answer : B

Structural testing is a type of testing that measures its effectiveness by tracking which lines of code were executed by the tests. Structural testing, also known as white-box testing or glass-box testing, is based on the internal structure, design, or implementation of the software. Structural testing aims to verify that the software meets the specified quality attributes, such as performance, security, reliability, or maintainability, by exercising the code paths, branches, statements, conditions, or data flows. Structural testing uses various coverage metrics, such as function coverage, line coverage, branch coverage, or statement coverage, to determine how much of the code has been tested and to identify any untested or unreachable parts of the code. Structural testing can be applied at any level of testing, such as unit testing, integration testing, system testing, or acceptance testing, but it is more commonly used at lower levels, where the testers have access to the source code.

The other options are not correct because they are not types of testing that measure their effectiveness by tracking which lines of code were executed by the tests. Acceptance testing is a type of testing that verifies that the software meets the acceptance criteria and the user requirements. Acceptance testing is usually performed by the end-users or customers, who may not have access to the source code or the technical details of the software. Acceptance testing is more concerned with the functionality, usability, or suitability of the software, rather than its internal structure or implementation. Integration testing is a type of testing that verifies that the software components or subsystems work together as expected. Integration testing is usually performed by the developers or testers, who may use both structural and functional testing techniques to check the interfaces, interactions, or dependencies between the components or subsystems. Integration testing is more concerned with the integration logic, data flow, or communication of the software, rather than its individual lines of code. Exploratory testing is a type of testing that involves simultaneous learning, test design, and test execution. Exploratory testing is usually performed by the testers, who use their creativity, intuition, or experience to explore the software and discover any defects, risks, or opportunities for improvement. Exploratory testing is more concerned with the behavior, quality, or value of the software, rather than its internal structure or implementation. Reference = ISTQB Certified Tester Foundation Level (CTFL) v4.0 syllabus, Chapter 4: Test Techniques, Section 4.3: Structural Testing Techniques, Pages 51-54; Chapter 1: Fundamentals of Testing, Section 1.4: Testing Throughout the Software Development Lifecycle, Pages 11-13; Chapter 3: Static Testing, Section 3.4: Exploratory Testing, Pages 40-41.