Software Testing Quality Control & Assurance 2 — Questions and Answers
Question 1: Which metric measures the percentage of defects found before software is released to production?
- Defect Removal Efficiency (DRE) (Correct answer)
- Mean Time Between Failures (MTBF)
- Defect Density
- Test Coverage Ratio
Correct answer: Defect Removal Efficiency (DRE)
Defect Removal Efficiency (DRE) measures the percentage of defects detected and removed before the product reaches the customer.
Question 2: In a cause-and-effect (Ishikawa) diagram, what are the main categories typically represented as 'bones'?
- Man, Machine, Method, Material, Measurement, Environment (Correct answer)
- Plan, Do, Check, Act
- Define, Measure, Analyze, Improve, Control
- Input, Process, Output, Feedback
Correct answer: Man, Machine, Method, Material, Measurement, Environment
The Ishikawa fishbone diagram organizes potential causes under the 6M categories: Man, Machine, Method, Material, Measurement, and Environment.
Question 3: A software team adopts pair reviews where two developers inspect code together in real time. This practice is best described as:
- Walkthrough
- Pair programming inspection
- Over-the-shoulder review (Correct answer)
- Formal inspection
Correct answer: Over-the-shoulder review
An over-the-shoulder review occurs when one developer watches another review or write code and provides real-time feedback.
Question 4: Which QA activity focuses on verifying that all identified defects have been corrected without introducing new issues?
- Regression testing
- Confirmation testing (Correct answer)
- Sanity testing
- Exploratory testing
Correct answer: Confirmation testing
Confirmation testing (also called re-testing) verifies that a specific defect has been fixed after a fix is applied.
Question 5: Which standard provides guidelines specifically for software process capability determination?
- ISO/IEC 15504 (SPICE) (Correct answer)
- ISO 9001
- IEEE 829
- CMMI
Correct answer: ISO/IEC 15504 (SPICE)
ISO/IEC 15504, known as SPICE (Software Process Improvement and Capability dEtermination), defines a framework for assessing software process capability.
Question 6: A QA engineer notices a test suite has 90% statement coverage but critical branch conditions remain untested. Which coverage type should be added?
- Decision/branch coverage (Correct answer)
- Path coverage
- Condition coverage
- Statement coverage
Correct answer: Decision/branch coverage
Decision (branch) coverage ensures every branch outcome (true/false) of each decision point is exercised, catching issues missed by statement coverage alone.
Question 7: In Six Sigma, what does the term 'sigma level' represent?
- The number of defects per unit produced
- The standard deviations between the process mean and the nearest specification limit (Correct answer)
- The percentage of variation caused by special causes
- The ratio of customer complaints to total deliveries
Correct answer: The standard deviations between the process mean and the nearest specification limit
Sigma level measures how many standard deviations fit between the process mean and the specification limit, with higher sigma indicating fewer defects.
Software Testing Quality Control & Assurance 2
Which metric measures the percentage of defects found before software is released to production?