According to the syllabus, the absence-of-errors fallacy is a common misconception that finding and fixing defects will ensure the success of a system. This fallacy ignores the fact that there may be other factors that affect user satisfaction and system value, such as usability, functionality, performance, reliability, security, etc. The answer D is correct because it is an example of the absence-of-errors fallacy. Since testing found very few defects, the system certainly will be successful. This statement assumes that defect detection is the only criterion for system success, which is not true. The other answers are incorrect because they are not examples of the absence-of-errors fallacy, but rather facts or challenges related to testing.

Component testing is a part of the V-Model, which is a development life cycle model that shows the relationship between each phase of development and its corresponding phase of testing. In this model, each level of testing (unit testing, integration testing, system testing, acceptance testing) has a corresponding level of development (component design, component integration, system design, requirements analysis). Component testing is the process of testing individual components or units of software in isolation from other components or systems. Component testing verifies that the components meet their functional and non-functional requirements and work as expected in their intended environment. Component testing is usually done by developers who have access to the component design and code specifications. You can find more information about component testing and the V-Model inSoftware Testing Foundations: A Study Guide for the Certified Tester Exam, Chapter 22.

Functional and structural tests are alternative test types that may be used separately or together at B. All test levels. Functional testing is a type of testing that verifies the functionality of the system or component under test against its requirements or specifications. Functional testing focuses on what the system or component does, not how it does it. Structural testing is a type of testing that verifies the structure or code of the system or component under test. Structural testing focuses on how the system or component does it, not what it does. Functional and structural testing can be used separately or together at any test level, such as unit testing, integration testing, system testing, acceptance testing, etc. Functional and structural testing can complement each other by providing different perspectives and coverage of the system or component under test. A detailed explanation of functional and structural testing can be found in [A Study Guide to the ISTQB Foundation Level 2018 Syllabus], pages 25-26.

Use case testing does not find defects caused by interaction of different components is the statement that is false about use case testing. Use case testing is a technique to create test cases based on use cases, which are descriptions of how a system interacts with one or more actors (users or other systems) to achieve a specific goal or function.Use case testing can find defects caused by interaction of different components, as use cases often involve multiple components working together to provide a service or functionality to an actor2explains use case testing as follows:

Use case testing is a technique that helps us identify test cases that exercise the whole system on a transaction by transaction basis from start to finish. It is a functional black box testing technique.

Use cases are prepared by analysts and domain experts who document the functional requirements of a system from an end-user perspective. Each use case typically has a mainstream scenario and may have alternate or exceptional scenarios that describe different paths or outcomes.

Use case testing can help to verify that all the interactions between actors and the system under test work as expected and meet the user requirements. It can also help to detect integration defects between different components or subsystems.

A, B, and D are correct statements about use case testing. Use case generally has a mainstream scenario and may have many alternate or exceptional scenarios (A), as use cases describe different paths or outcomes depending on various conditions or events. A use case can be defined at different levels of abstraction, such as user goal level, summary level, subfunction level, etc., but not at the abstract level detached from the implementation or at the system level describing a set of executed functions (B), as use cases always describe interactions between actors and systems rather than abstract concepts or functions. Each use case has preconditions which need to be met for the use case to work successfully (D), as preconditions specify what must be true before a use case can begin.

In the context of software testing, the correct sequence of events typically starts with amistake, which is a human error made during the software development process. This mistake can lead to afaultin the code, which is a defect or bug that exists in the software. If this fault is executed, it may cause afailure, which is an instance where the software does not perform its intended function.