Lecture 4 - COMP1551

What are the four main principles of Object-Oriented Programming (OOP)?

• Encapsulation, Classes, Methods, Objects

• Encapsulation, Abstraction, Inheritance, Polymorphism

• Polymorphism, Methods, Objects, Functions

• Data, Objects, Classes, Modifiers

What is the purpose of encapsulation in OOP?

• To allow all parts of a program to access a class’s data freely

• To wrap data and functionality into a single entity and restrict access

• To make all class members public

• To remove data from a class

Which of the following access modifiers restricts access to only within the same class?

• public

• protected

• private

• internal

Which OOP principle involves specifying what data and functionality should be exposed and what should remain hidden?

• Abstraction

• Encapsulation

• Inheritance

• Polymorphism

Which statement about inheritance is true?

• It allows multiple base classes for a single derived class in C#

• It enables code reuse by creating a base class and derived classes

• It prevents a derived class from accessing methods of the base class

• It only applies to abstract classes

Which OOP concept allows multiple classes to share the same method name but provide different implementations?

• Encapsulation

• Abstraction

• Inheritance

• Polymorphism

What does the term “is-a” relationship refer to in OOP?

• Encapsulation

• Inheritance

• Abstraction

• Static classes

Which type of polymorphism is achieved when methods share the same name but differ in parameters?

• Static polymorphism

• Dynamic polymorphism

• Inheritance

• Encapsulation

What happens when an abstract method is declared in a base class?

• The method can be overridden optionally

• The method is automatically inherited without modification

• All derived classes must provide their own implementation of the method

• The method cannot be inherited

Which of the following statements about abstract classes is true?

• Abstract classes can be instantiated like regular classes

• Abstract classes cannot contain abstract methods

• Abstract classes must have only abstract methods

• Abstract classes can define method signatures that derived classes must implement