OOP Fundamentals: 15 MCQs with answers

A · Data and methods are combined into objects.

OOP is based on objects that combine data and methods, unlike procedural programming where they are separate.

B · Compilation

Compilation is not a pillar of OOP. The six pillars are Class, Object, Encapsulation, Abstraction, Inheritance, and Polymorphism.

A · A blueprint for creating objects.

A class is a blueprint that defines the attributes and behaviors of objects, but it does not hold data directly.

D · Abstraction

Abstraction focuses on what an object does rather than how it does it, hiding complex details.

B · Code reusability

Inheritance allows a child class to acquire properties and methods from a parent class, promoting code reusability.

D · Many forms

Polymorphism literally means 'many forms' and allows objects to behave differently based on their type.

C · An instance of a class.

An object is an instance of a class, created from the class blueprint, and holds its own data.

A · True

Polymorphism enables methods to have different implementations depending on the object calling them.

A · To bundle data and methods, restricting direct access.

Encapsulation bundles data and methods into a single unit and restricts direct access using access modifiers.

B · It provides data security.

Encapsulation enhances security by hiding internal state and allowing access only through methods.

B · Parallel

The source lists single, multiple, multilevel, hierarchical, and hybrid inheritance, but not parallel.

A · Method overloading and method overriding

Polymorphism can be achieved through method overloading (compile-time) and method overriding (runtime).

C · Modular design

OOP promotes modular design, making development and maintenance easier.

D · Inheritance

Inheritance establishes an 'is-a' relationship where a child class inherits from a parent class.

B · False

Encapsulation is about bundling data and methods and restricting access, while abstraction is about hiding complex details and showing only essential features.