D480 ITSW 3151 Software Design &
Quality Assurance
Objective Assessment Review
(Questions & Solutions)
2025
©2025
, Question 1
An enterprise system is being redesigned to improve maintainability.
Which SOLID principle specifically advises that a class should have only
one reason to change?
- A. Open/Closed Principle
- B. Single Responsibility Principle
- C. Liskov Substitution Principle
- D. Interface Segregation Principle
ANS: B
Rationale: The Single Responsibility Principle (SRP) states that a class
should have one, and only one, reason to change. This reduces
complexity by ensuring that each class addresses a single functionality or
concern.
---
Question 2
In a scenario where a large-scale distributed system must be designed to
handle independent feature deployments and minimize
interdependencies, which architectural style is most beneficial?
- A. Monolithic architecture
- B. Layered architecture
- C. Microservices architecture
- D. Client–server architecture
ANS: C
Rationale: A microservices architecture decomposes an application into
small, loosely coupled services that can be deployed and scaled
independently. This style is particularly advantageous for accommodating
continuous delivery and reducing the impact of changes.
---
©2025
, Question 3
A team of software engineers must add new behavior to objects at
runtime without altering existing class code. Which design pattern best
addresses this need?
- A. Observer Pattern
- B. Strategy Pattern
- C. Decorator Pattern
- D. Adapter Pattern
ANS: C
Rationale: The Decorator Pattern allows behavior to be added
dynamically by “wrapping” an object with a decorator class. This
preserves the existing code while enabling enhanced functionality at
runtime.
---
Question 4
When automating regression tests for a continuously evolving
application, which technique best ensures that changes do not
reintroduce previously fixed defects?
- A. Smoke testing
- B. Performance testing
- C. Regression testing using automated test suites
- D. Exploratory testing
ANS: C
Rationale: Regression testing—especially when automated—ensures
that code modifications do not break or degrade previously working
functionality, making it crucial for continuous integration and
deployment environments.
---
©2025
, Question 5
In assessing software quality for a safety‑critical system, which quality
assurance approach involves formal, structured reviews with a team of
experts to examine software artifacts?
- A. Ad hoc code reviews
- B. Fagan Inspection
- C. Automated unit testing
- D. Pair programming
ANS: B
Rationale: Fagan Inspection is a structured review process used to
detect defects early by having a formal, team‑based examination of
design documents or code, making it particularly important for
safety‑critical systems.
---
Question 6
Which metric is most relevant when measuring the reliability and quality
of a software product during its testing phase?
- A. Lines of code (LOC)
- B. Defect density
- C. Code churn
- D. Cyclomatic complexity
ANS: B
Rationale: Defect density—defined as the number of defects per unit
size of the software—is a key measure of software reliability and quality,
allowing teams to monitor improvements and risk areas throughout the
development lifecycle.
---
Question 7
A software product's design undergoes multiple iterations, and each
©2025
Quality Assurance
Objective Assessment Review
(Questions & Solutions)
2025
©2025
, Question 1
An enterprise system is being redesigned to improve maintainability.
Which SOLID principle specifically advises that a class should have only
one reason to change?
- A. Open/Closed Principle
- B. Single Responsibility Principle
- C. Liskov Substitution Principle
- D. Interface Segregation Principle
ANS: B
Rationale: The Single Responsibility Principle (SRP) states that a class
should have one, and only one, reason to change. This reduces
complexity by ensuring that each class addresses a single functionality or
concern.
---
Question 2
In a scenario where a large-scale distributed system must be designed to
handle independent feature deployments and minimize
interdependencies, which architectural style is most beneficial?
- A. Monolithic architecture
- B. Layered architecture
- C. Microservices architecture
- D. Client–server architecture
ANS: C
Rationale: A microservices architecture decomposes an application into
small, loosely coupled services that can be deployed and scaled
independently. This style is particularly advantageous for accommodating
continuous delivery and reducing the impact of changes.
---
©2025
, Question 3
A team of software engineers must add new behavior to objects at
runtime without altering existing class code. Which design pattern best
addresses this need?
- A. Observer Pattern
- B. Strategy Pattern
- C. Decorator Pattern
- D. Adapter Pattern
ANS: C
Rationale: The Decorator Pattern allows behavior to be added
dynamically by “wrapping” an object with a decorator class. This
preserves the existing code while enabling enhanced functionality at
runtime.
---
Question 4
When automating regression tests for a continuously evolving
application, which technique best ensures that changes do not
reintroduce previously fixed defects?
- A. Smoke testing
- B. Performance testing
- C. Regression testing using automated test suites
- D. Exploratory testing
ANS: C
Rationale: Regression testing—especially when automated—ensures
that code modifications do not break or degrade previously working
functionality, making it crucial for continuous integration and
deployment environments.
---
©2025
, Question 5
In assessing software quality for a safety‑critical system, which quality
assurance approach involves formal, structured reviews with a team of
experts to examine software artifacts?
- A. Ad hoc code reviews
- B. Fagan Inspection
- C. Automated unit testing
- D. Pair programming
ANS: B
Rationale: Fagan Inspection is a structured review process used to
detect defects early by having a formal, team‑based examination of
design documents or code, making it particularly important for
safety‑critical systems.
---
Question 6
Which metric is most relevant when measuring the reliability and quality
of a software product during its testing phase?
- A. Lines of code (LOC)
- B. Defect density
- C. Code churn
- D. Cyclomatic complexity
ANS: B
Rationale: Defect density—defined as the number of defects per unit
size of the software—is a key measure of software reliability and quality,
allowing teams to monitor improvements and risk areas throughout the
development lifecycle.
---
Question 7
A software product's design undergoes multiple iterations, and each
©2025
