1. Which of the following OOP principles is used when a child class reuses
methods from a parent class?
A. Abstraction
B. Encapsulation
C. Inheritance
D. Polymorphism
Answer: C) Inheritance
Rationale: Inheritance allows a subclass to inherit methods and properties from a
superclass.
2. Which of the following is true about the "abstract" keyword?
A. It is used to create instances of a class
B. It defines the behavior of a method in a class
C. It indicates that a class cannot have any methods
D. It defines methods that must be implemented by derived classes
Answer: D) It defines methods that must be implemented by derived classes
,Rationale: The abstract keyword is used to define methods in an abstract class that
must be implemented by any non-abstract subclass.
3. What is the main purpose of the protected access modifier?
A. To allow access to class members from the same class and its subclasses
B. To restrict access to class members to only within the class
C. To allow access to class members from anywhere in the program
D. To allow access to class members from only within its package
Answer: A) To allow access to class members from the same class and its
subclasses
Rationale: The protected access modifier allows access to class members from the
class itself and its subclasses.
4. What does the private access modifier mean in OOP?
A. The member is accessible only within its class
B. The member is accessible from any class
C. The member is accessible from its package only
D. The member is accessible from subclasses
, Answer: A) The member is accessible only within its class
Rationale: The private access modifier restricts access to members of a class from
any other class except the class where it is declared.
5. Which of the following is a feature of object-oriented programming?
A. Data is hidden
B. Data is manipulated directly
C. Functions are not used
D. Programs are written in a procedural way
Answer: A) Data is hidden
Rationale: One of the key features of OOP is data encapsulation, which means data
is hidden from outside access and can only be accessed through public methods.
6. Which keyword is used to prevent a class from being inherited in OOP?
A. static
B. private
C. final
D. abstract
methods from a parent class?
A. Abstraction
B. Encapsulation
C. Inheritance
D. Polymorphism
Answer: C) Inheritance
Rationale: Inheritance allows a subclass to inherit methods and properties from a
superclass.
2. Which of the following is true about the "abstract" keyword?
A. It is used to create instances of a class
B. It defines the behavior of a method in a class
C. It indicates that a class cannot have any methods
D. It defines methods that must be implemented by derived classes
Answer: D) It defines methods that must be implemented by derived classes
,Rationale: The abstract keyword is used to define methods in an abstract class that
must be implemented by any non-abstract subclass.
3. What is the main purpose of the protected access modifier?
A. To allow access to class members from the same class and its subclasses
B. To restrict access to class members to only within the class
C. To allow access to class members from anywhere in the program
D. To allow access to class members from only within its package
Answer: A) To allow access to class members from the same class and its
subclasses
Rationale: The protected access modifier allows access to class members from the
class itself and its subclasses.
4. What does the private access modifier mean in OOP?
A. The member is accessible only within its class
B. The member is accessible from any class
C. The member is accessible from its package only
D. The member is accessible from subclasses
, Answer: A) The member is accessible only within its class
Rationale: The private access modifier restricts access to members of a class from
any other class except the class where it is declared.
5. Which of the following is a feature of object-oriented programming?
A. Data is hidden
B. Data is manipulated directly
C. Functions are not used
D. Programs are written in a procedural way
Answer: A) Data is hidden
Rationale: One of the key features of OOP is data encapsulation, which means data
is hidden from outside access and can only be accessed through public methods.
6. Which keyword is used to prevent a class from being inherited in OOP?
A. static
B. private
C. final
D. abstract
