0 — Test 599

Correct Answer: B. Common coupling
Explanation: Global data creates hidden dependencies between every module that uses it. ALSO KNOW (related points): • Which design pattern ensures that a class has only one instance and provides a global point of access to it? → Singleton • Which diagram shows the hierarchy of modules and the data passed between them in structured design? → Structure chart

Correct Answer: B. A class should have only one reason to change
Explanation: A common confusion is with the Singleton pattern, which is unrelated.

Correct Answer: D. Software entities should be open for extension but closed for modification
Explanation: New behavior is added through extension (inheritance or composition) rather than by editing existing code.

Correct Answer: A. Objects of a subclass must be usable wherever the base class is expected, without breaking correctness
Explanation: The classic violation is Square inheriting from Rectangle and breaking the expectations of setWidth. ALSO KNOW (related points): • In SOLID, what does the 'S' (Single Responsibility Principle) state? → A class should have only one reason to change • What does the Open/Closed Principle state? → Software entities should be open for extension but closed for modification • What is the main idea of the DRY principle? → Don't Repeat Yourself: each piece of knowledge should have a single representation

Correct Answer: C. Top-down design (stepwise refinement)
Explanation: Bottom-up design builds low-level components first and then assembles them.

Correct Answer: B. Singleton
Explanation: Observer handles one-to-many notifications. Adapter converts one interface into another.

Correct Answer: C. Observer
Explanation: The Observer pattern is also called Publish/Subscribe.

Correct Answer: C. Don't Repeat Yourself: each piece of knowledge should have a single representation
Explanation: Duplicated logic tends to drift out of sync when only one copy is fixed.

Correct Answer: B. Verification asks 'are we building the product right?'; validation asks 'are we building the right product?'
Explanation: Verification checks conformance to the specification, for example through reviews. Validation checks that the product meets the user's real needs. ALSO KNOW (related points): • In a formal inspection, who leads the meeting? → A trained moderator • Which formal review is the most structured, with defined roles, checklists, and metrics? → Inspection

Correct Answer: C. Testing shows the presence of defects, not their absence
Explanation: Other ISTQB principles include early testing, defect clustering, and the pesticide paradox. ALSO KNOW (related points): • What does the 'pesticide paradox' in testing refer to? → Running the same tests repeatedly eventually stops finding new defects • Which statement about 100% code coverage is correct? → It does not guarantee the absence of bugs; for example, missing requirements or wrong logic can still pass • Which approach designs and executes tests at the same time, learning about the system as you go? → Exploratory testing