CAST Software Testing Fundamentals 3 — Questions and Answers
Question 1: What distinguishes verification from validation?
- Verification checks if we built it right; validation checks if we built the right thing (Correct answer)
- Verification is done by users; validation by developers
- Verification only applies to hardware
- They are identical processes
Correct answer: Verification checks if we built it right; validation checks if we built the right thing
Verification confirms the product meets specifications, while validation confirms it meets user needs.
Question 2: Which level of testing checks the interaction between integrated modules?
- Unit testing
- Integration testing (Correct answer)
- System testing
- Acceptance testing
Correct answer: Integration testing
Integration testing verifies that combined modules work together correctly through their interfaces.
Question 3: What is a test oracle?
- A tool that generates random test data
- A mechanism for determining the expected result of a test (Correct answer)
- A database of past defects
- An automated test runner
Correct answer: A mechanism for determining the expected result of a test
A test oracle is the source used to decide whether a test's actual output is correct.
Question 4: Which statement about exhaustive testing is correct?
- It is always achievable with enough time
- It is usually impractical due to too many possible inputs (Correct answer)
- It guarantees zero defects
- It is required by all standards
Correct answer: It is usually impractical due to too many possible inputs
Testing every possible input combination is generally infeasible, so testing focuses on representative cases.
Question 5: A defect found during testing but caused by a missing requirement is best classified as a problem in which phase?
- Coding
- Requirements (Correct answer)
- Deployment
- Maintenance
Correct answer: Requirements
A missing requirement originates in the requirements phase, even if discovered later during testing.
Question 6: What does 'test coverage' measure?
- The number of testers on a project
- The extent to which the code or requirements are exercised by tests (Correct answer)
- How long testing takes
- The cost of the testing effort
Correct answer: The extent to which the code or requirements are exercised by tests
Test coverage quantifies how much of the code, requirements, or functionality has been tested.
Question 7: Why is early defect detection generally cheaper?
- Early defects are always trivial
- The cost to fix a defect rises as it progresses through later phases (Correct answer)
- Testers cost less early in a project
- Early defects do not need documentation
Correct answer: The cost to fix a defect rises as it progresses through later phases
Fixing a defect costs more in later phases because it requires reworking more dependent work.
CAST Software Testing Fundamentals 3
What distinguishes verification from validation?