Question 1
What is polymorphism in Object-Oriented Programming (OOP)?
1
The process of restricting access to certain members of a class.
2
The ability to inherit properties from a base class.
3
The mechanism of wrapping data and methods into a single unit.
4
The ability to use the same function name for different functionalities.
Question 2
What are the types of polymorphism in OOP?
1
Public and Private
2
Inheritance and Encapsulation
3
Static and Dynamic
4
Single and Multiple
Question 3
Which of the following is an example of compile-time polymorphism?
1
Function Overloading
2
Abstract Classes
3
Function Overriding
4
Interfaces
Question 4
What is the difference between method overloading and method overriding?
1
Overloading requires inheritance, overriding does not
2
Overloading occurs in the same class, overriding occurs in a derived class
3
Overloading is runtime polymorphism, overriding is compile-time polymorphism
4
Overloading happens in a subclass, overriding happens in the same class
Question 5
Which statement about polymorphism is correct?
1
Polymorphism enables a function to be used for different types of objects.
2
Polymorphism is only applicable to function overloading.
3
Polymorphism prevents method overriding.
4
Polymorphism allows multiple classes to have the same properties.
Question 6
What is the key feature of runtime polymorphism?
1
Compile-time resolution
2
No inheritance required
3
Dynamic method dispatch
4
Method overloading
Question 7
Which of the following statements about function overloading and function overriding is correct?
1
Function overloading occurs at runtime, while function overriding occurs at compile time
2
Function overloading is resolved at compile-time, while function overriding is resolved at runtime
3
Function overloading requires inheritance, while function overriding does not
4
Function overriding does not support dynamic binding
Question 8
What is method overriding in Java?
1
Defining a method with the same name and parameters in a child class
2
Making a method static
3
Changing the return type of an existing method
4
Declaring a new method with the same name in the same class
Question 9
Which keyword is used in Java to prevent method overriding?
1
final
2
abstract
3
static
4
super
Question 10
What will be the output of the following Java program?
class A {
void display() { System.out.println("Class A"); }
}
class B extends A {
void display() { System.out.println("Class B"); }
}
public class Main {
public static void main(String[] args) {
A obj = new B();
obj.display();
}
}1
Compilation Error
2
Class A
3
Runtime Error
4
Class B
Question 11
Which of the following statements is true about operator overloading in C++?
1
It is a type of compile-time polymorphism
2
It is achieved using function overloading
3
It allows redefining how operators work for user-defined types
4
All of the above
Question 12
In C++, which keyword is used to achieve runtime polymorphism?
1
override
2
friend
3
virtual
4
static
Question 13
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 14
How does Java implement runtime polymorphism?
1
Dynamic method dispatch
2
Function overloading
3
Early binding
4
Virtual function table (vtable)
Question 15
What is a virtual function in C++?
1
A function that is resolved at runtime
2
A function that cannot be overridden
3
A function that supports operator overloading
4
A function with no implementation
Question 16
What is the role of the vtable in C++?
1
It stores pointers to virtual functions.
2
It speeds up compile-time polymorphism.
3
It stores a list of all functions in a class.
4
It prevents method overriding.
Question 17
Which keyword in Java is used to call the parent class method explicitly in method overriding?
1
super
2
parent
3
base
4
override
Question 18
What will be the output of the following program?
#include <iostream>
using namespace std;
class Base {
public:
virtual void show() { cout << "Base"; }
};
class Derived : public Base {
public:
void show() { cout << "Derived"; }
};
int main() {
Base b;
Derived d;
Base* ptr = &b;
ptr->show();
return 0;
}1
Undefined Behavior
2
Derived
3
Base
4
Compilation Error
Question 19
What will be the output of the following program?
#include <iostream>
using namespace std;
class Base {
public:
virtual void show() { cout << "Base"; }
};
class Derived : public Base {
public:
void show() { cout << "Derived"; }
};
int main() {
Base b;
Derived d;
Base* ptr = &d;
ptr->show();
return 0;
}1
Undefined Behavior
2
Derived
3
Base
4
Compilation Error
Question 20
What will be the output of the following program?
#include <iostream>
using namespace std;
class Base {
public:
virtual void show() { cout << "Base"; }
};
class Derived : public Base {
public:
void show() { cout << "Derived"; }
};
int main() {
Base b;
Derived d;
Derived* ptr = &b;
ptr->show();
return 0;
}1
Undefined Behavior
2
Error
3
Derived
4
Base
Question 21
Which of the following is true about abstract classes in C#?
1
An abstract class can have concrete methods.
2
Abstract classes can be instantiated.
3
Abstract classes must have at least one abstract method.
4
Interfaces and abstract classes are the same.
Question 22
What happens when a base class function is declared as virtual in C++?
1
The function cannot be overridden in derived classes
2
The function cannot have a body
3
The function call is resolved at runtime using vtable
4
The function call is resolved at compile-time
Question 23
What is true about method overriding in Java?
1
A method cannot be overridden if it is declared static
2
Overriding methods must have the same return type and parameters
3
Overriding is determined at compile time
4
The return type of the overriding method can be a subclass of the return type of the overridden method
Question 24
Which keyword prevents method overriding in C#?
1
abstract
2
private
3
sealed
4
final
Question 25
What happens if a class contains at least one pure virtual function in C++?
1
It can be instantiated normally
2
It becomes an abstract class
3
It cannot have constructors
4
It does not support polymorphism
Question 26
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
Runtime error
2
The derived class method is called
3
Compilation error
4
The base class method is called
Question 27
What will happen if a C++ derived class does not override a virtual function of the base class?
1
Compilation error
2
Undefined behavior
3
The program crashes
4
Runtime Error
5
The base class function is called
Question 28
Which statement is true about interfaces and abstract classes?
1
Abstract classes cannot have concrete methods
2
An abstract class can have both abstract and concrete methods
3
Interfaces cannot be implemented by multiple classes
4
Interfaces can have constructors
Question 29
Which principle of OOP is illustrated by defining different methods with the same name but different parameters?
1
Polymorphism
2
Encapsulation
3
Abstraction
4
Inheritance
Question 30
Which concept in OOP allows for the same function to be used in different ways based on the object it is associated with?
1
Polymorphism
2
Abstraction
3
Encapsulation
4
Inheritance