Question 1
Which statement is true about interfaces and abstract classes?
1
Interfaces cannot be implemented by multiple classes
2
Abstract classes cannot have concrete methods
3
Interfaces can have constructors
4
An abstract class can have both abstract and concrete methods
Question 2
What is the primary purpose of abstraction in Object-Oriented Programming (OOP)?
1
To provide direct access to data
2
To hide implementation details and show only essential features
3
To make data more accessible
4
To increase code complexity
Question 3
Which OOP principle is most closely related to abstraction?
1
Encapsulation
2
Inheritance
3
Polymorphism
4
None of the above
Question 4
What is the primary purpose of abstraction in Object-Oriented Programming (OOP)?
1
An abstract class can be instantiated
2
An abstract class must have at least one abstract method
3
An abstract class cannot have constructors
4
An abstract class can have both abstract and non-abstract methods
Question 5
What is the difference between abstraction and encapsulation?
1
Both are the same
2
Abstraction protects data, while encapsulation hides implementation details
3
Abstraction hides implementation details, while encapsulation protects data
4
Encapsulation is a subclass of abstraction
Question 6
Which of the following best describes an abstract method?
1
A method that is private and cannot be accessed
2
A method that has no body and must be implemented in derived classes
3
A method that is final and cannot be overridden
4
A method that cannot be inherited
Question 7
Which of the following is an advantage of using abstraction?
1
Increased code reusability
2
Reduced complexity
3
Easier maintenance and scalability
4
All of the above
Question 8
What is abstract class in C++?
1
Class from which any class is derived
2
Class specifically used as a base class with atleast one pure virtual functions
3
Any Class in C++ is an abstract class
4
Class specifically used as a base class with atleast one virtual functions
Question 9
What is an abstract class in Java?
1
A class that cannot be instantiated
2
A class that must contain at least one abstract method
3
A class that allows method overriding
4
All of the above
Question 10
Which of the following is true about abstract classes in C#?
1
Abstract classes must have at least one abstract method.
2
An abstract class can have concrete methods.
3
Interfaces and abstract classes are the same.
4
Abstract classes can be instantiated.
Question 11
What happens if a class contains at least one pure virtual function in C++?
1
It cannot have constructors
2
It becomes an abstract class
3
It does not support polymorphism
4
It can be instantiated normally
Question 12
What is the default behavior if a base class pointer points to a derived class object but does not use virtual functions in C++?
1
The derived class method is called
2
Compilation error
3
Runtime error
4
The base class method is called
Question 13
What will happen if a C++ derived class does not override a virtual function of the base class?
1
Undefined behavior
2
The base class function is called
3
The program crashes
4
Compilation error
5
Runtime Error
Question 14
What is Encapsulation in Object-Oriented Programming (OOP)?
1
Allowing direct access to all data members of a class
2
Hiding the implementation details and exposing only the necessary functionality
3
Using multiple inheritance to combine functionalities
4
Writing all code in a single function
Question 15
Which access specifier should be used to achieve Encapsulation in a class?
1
Private
2
Static
3
Public
4
Protected
Question 16
Which of the following statements is true regarding Encapsulation?
1
Encapsulation forces all class members to be static
2
Encapsulation is a way to achieve inheritance
3
Encapsulation helps in data abstraction and security
4
Encapsulation does not allow defining class members as private
Question 17
What is the primary difference between Encapsulation and Abstraction?
1
Encapsulation is only applicable to variables, while abstraction applies to methods
2
Encapsulation is not used in real-world applications, while abstraction is
3
Encapsulation hides implementation details, while abstraction hides complexity
4
Abstraction deals with private members only, while encapsulation does not
Question 18
How is abstraction implemented in Java?
1
Using static methods
2
Using instance variables
3
Using abstract classes and interfaces
4
Using constructors
Question 19
Which of the following statements about interfaces in Java is true?
1
An interface can have final methods
2
A class can implement only one interface
3
An interface can have constructors
4
An interface supports multiple inheritance
Question 20
What keyword is used to define an abstract class in C++?
1
virtual
2
abstract
3
interface
4
class
Question 21
Which concept allows abstraction in Python?
1
The lambda function
2
The staticmethod decorator
3
The @override decorator
4
The @abstractmethod decorator