Software Testing Case Studies & Practical Application 5 — Questions and Answers
Question 1: A test team is asked to certify that a medical device software meets FDA 21 CFR Part 11 requirements. This is an example of:
- Operational acceptance testing
- Regulatory compliance testing (Correct answer)
- Compatibility testing
- Regression testing
Correct answer: Regulatory compliance testing
Regulatory compliance testing verifies that software meets the specific rules, standards, or regulations mandated by governing bodies such as the FDA.
Question 2: A defect is reproducible on the tester's machine but not on the developer's machine. The most productive next step is:
- Close the defect as 'not reproducible'
- Compare environment configurations between the two machines to identify differences (Correct answer)
- Rerun the test 10 more times
- Escalate immediately to senior management
Correct answer: Compare environment configurations between the two machines to identify differences
Environment differences—such as OS version, configuration, or dependencies—are the most common cause of 'works on my machine' issues, so comparing environments is the logical next step.
Question 3: A QA lead must recommend a test approach for a project where requirements change frequently. Which approach provides the best adaptability?
- Waterfall-based test planning with fixed test cases
- Risk-based testing combined with exploratory testing sessions (Correct answer)
- Exhaustive scripted test case execution only
- Testing deferred until requirements are finalized
Correct answer: Risk-based testing combined with exploratory testing sessions
Risk-based and exploratory testing adapt well to changing requirements because they prioritize by risk and rely on tester judgment rather than rigid scripts.
Question 4: A team implements test-driven development (TDD). A developer writes a test for a new function, runs it, and it passes immediately without writing the implementation. What does this indicate?
- The function is already implemented correctly
- The test is likely not testing the right thing and may be a false positive (Correct answer)
- TDD has been completed successfully for this function
- The CI pipeline has a caching issue
Correct answer: The test is likely not testing the right thing and may be a false positive
In TDD, a new test should fail first (red phase); if it passes immediately before implementation, the test is probably not actually exercising the intended behavior.
Question 5: A social media platform experiences degraded performance when a viral post drives 10x normal traffic suddenly. Which test type is specifically designed to simulate this scenario?
- Volume testing
- Soak testing
- Spike testing (Correct answer)
- Stress testing
Correct answer: Spike testing
Spike testing evaluates system behavior under sudden, dramatic increases in load and then monitors recovery once the spike subsides.
Question 6: During code review, a tester notices a SQL query builds a WHERE clause by concatenating user input directly. What defect category should be raised?
- Performance defect
- SQL injection vulnerability (Correct answer)
- Boundary value defect
- Usability defect
Correct answer: SQL injection vulnerability
Directly concatenating user input into SQL queries creates an SQL injection vulnerability, one of the most critical OWASP Top 10 security risks.
Question 7: A team wants to measure the effectiveness of its test suite by intentionally introducing small code faults and checking if tests detect them. This technique is called:
- Code coverage analysis
- Fault injection testing
- Mutation testing (Correct answer)
- Static analysis
Correct answer: Mutation testing
Mutation testing deliberately introduces small syntactic changes (mutants) to source code and measures what percentage of mutants the test suite detects (kills).
Software Testing Case Studies & Practical Application 5
A test team is asked to certify that a medical device software meets FDA 21 CFR Part 11 requirements.
This is an example of: