Object-Oriented Programming Quiz

Question 1

Which OOP principle bundles data and the methods that operate on it, hiding internal state?

Accepted Answer

Encapsulation

Answer

Inheritance

Answer

Polymorphism

Answer

Abstraction

Question 2

Method overriding is an example of…

Accepted Answer

Runtime (dynamic) polymorphism

Answer

Compile-time polymorphism

Answer

Encapsulation

Answer

Composition

Question 3

What is the difference between an abstract class and an interface (in most languages)?

Accepted Answer

An abstract class can have implemented methods and state; an interface traditionally declares a contract only

Answer

They are identical

Answer

An interface can be instantiated but an abstract class cannot

Answer

Abstract classes support multiple inheritance but interfaces do not

Question 4

"Favor composition over inheritance" advises you to…

Accepted Answer

Build behavior by combining objects rather than deep inheritance hierarchies

Answer

Never use classes

Answer

Always inherit from at least two classes

Answer

Avoid interfaces

Question 5

Polymorphism literally means…

Accepted Answer

Many forms

Answer

Single form

Answer

No form

Answer

Hidden form

Question 6

In the SOLID principles, what does the "S" stand for?

Accepted Answer

Single Responsibility Principle

Answer

Separation Principle

Answer

State Principle

Answer

Static Principle

Question 7

Abstraction is best described as…

Accepted Answer

Exposing essential features while hiding implementation complexity

Answer

Copying code between classes

Answer

Making all fields public

Answer

Running methods concurrently

Question 8

What does the Liskov Substitution Principle require?

Accepted Answer

Subtypes must be substitutable for their base types without breaking correctness

Answer

Every class must have a substitute

Answer

Interfaces must be small

Answer

Classes must not depend on abstractions

Object-Oriented Programming quiz