C++ and OOP MCQ Test

1. C++ was originally known by which name?

• A. C with Classes
• B. Advanced C
• C. Object C
• D. New C

Answer: C with Classes

2. Which of these is NOT a feature of object-oriented programming?

• A. Encapsulation
• B. Inheritance
• C. Polymorphism
• D. Compilation

Answer: Compilation

3. What is a class in C++?

• A. A blueprint for creating objects
• B. A type of loop
• C. A memory address
• D. A built-in function

Answer: A blueprint for creating objects

4. What is an object in object-oriented programming?

• A. A copy of a function
• B. An instance of a class
• C. A data type
• D. A header file

Answer: An instance of a class

5. Which OOP concept hides internal data and exposes only what is needed?

• A. Inheritance
• B. Encapsulation
• C. Polymorphism
• D. Recursion

Answer: Encapsulation

6. Which OOP concept lets one class acquire the properties of another?

• A. Encapsulation
• B. Inheritance
• C. Abstraction
• D. Overloading

Answer: Inheritance

7. Which OOP concept means 'one name, many forms'?

• A. Inheritance
• B. Polymorphism
• C. Encapsulation
• D. Modularity

Answer: Polymorphism

8. Which OOP concept shows only essential features and hides the details?

• A. Abstraction
• B. Inheritance
• C. Overriding
• D. Linking

Answer: Abstraction

9. Which access specifier makes members accessible from anywhere?

• A. private
• B. protected
• C. public
• D. internal

Answer: public

10. What is the default access specifier for members of a C++ class?

• A. public
• B. private
• C. protected
• D. static

Answer: private

11. What is the default access specifier for members of a C++ struct?

• A. private
• B. public
• C. protected
• D. none

Answer: public

12. Which access specifier allows access in derived classes but not outside?

• A. public
• B. private
• C. protected
• D. friend

Answer: protected

13. What is a constructor in C++?

• A. A function that destroys an object
• B. A special member function called when an object is created
• C. A type of pointer
• D. A loop control statement

Answer: A special member function called when an object is created

14. What name must a constructor have?

• A. init
• B. main
• C. The same name as the class
• D. construct

Answer: The same name as the class

15. What does a constructor return?

• A. An integer
• B. A pointer to the object
• C. Nothing — it has no return type
• D. A boolean

Answer: Nothing — it has no return type

16. Which symbol prefixes a destructor name in C++?

• A. #
• B. ~
• C. !
• D. @

Answer: ~

17. When is a destructor called?

• A. When the object is created
• B. When the object goes out of scope or is deleted
• C. At program start
• D. Before every method call

Answer: When the object goes out of scope or is deleted

18. How many destructors can a class have?

• A. Only one
• B. Two
• C. As many as needed
• D. None

Answer: Only one

19. What is a copy constructor used for?

• A. To create an object from another object of the same class
• B. To delete an object
• C. To copy a file
• D. To convert data types

Answer: To create an object from another object of the same class

20. What is function overloading?

• A. Calling a function too many times
• B. Several functions with the same name but different parameters
• C. A function that calls itself
• D. A function with no return type

Answer: Several functions with the same name but different parameters

21. Which of these can NOT be used to distinguish overloaded functions?

• A. Number of parameters
• B. Types of parameters
• C. Return type alone
• D. Order of parameters

Answer: Return type alone

22. What is operator overloading?

• A. Using too many operators
• B. Giving an existing operator a new meaning for user-defined types
• C. Removing an operator
• D. Changing operator precedence

Answer: Giving an existing operator a new meaning for user-defined types

23. Which operator can NOT be overloaded in C++?

• A. +
• B. ==
• C. ::
• D. []

Answer: ::

24. Which keyword declares a function that can be redefined in a derived class?

• A. static
• B. virtual
• C. friend
• D. inline

Answer: virtual

25. What is function overriding?

• A. Two functions with the same name in one class
• B. A derived class redefining a base class function
• C. Calling a function repeatedly
• D. Deleting a function

Answer: A derived class redefining a base class function

26. What is a pure virtual function?

• A. A function with no parameters
• B. A virtual function declared with = 0 and no body in the base class
• C. A function that returns void
• D. A private function

Answer: A virtual function declared with = 0 and no body in the base class

27. A class containing at least one pure virtual function is called what?

• A. Final class
• B. Abstract class
• C. Static class
• D. Friend class

Answer: Abstract class

28. Can an abstract class be instantiated directly?

• A. Yes, always
• B. No, it cannot
• C. Only with new
• D. Only inside main()

Answer: No, it cannot

29. Which type of polymorphism is resolved at compile time?

• A. Run-time polymorphism
• B. Compile-time polymorphism
• C. Dynamic binding
• D. Late binding

Answer: Compile-time polymorphism

30. Virtual functions are an example of which kind of binding?

• A. Early binding
• B. Late (dynamic) binding
• C. Static binding
• D. No binding

Answer: Late (dynamic) binding

31. What is a friend function?

• A. A function inside another class
• B. A non-member function granted access to a class's private members
• C. A recursive function
• D. An overloaded function

Answer: A non-member function granted access to a class's private members

32. Which inheritance type has one derived class from one base class?

• A. Multiple
• B. Single
• C. Hierarchical
• D. Hybrid

Answer: Single

33. Which inheritance type has one class derived from more than one base class?

• A. Single
• B. Multiple
• C. Multilevel
• D. Hierarchical

Answer: Multiple

34. Which inheritance type has a chain such as A → B → C?

• A. Multiple
• B. Multilevel
• C. Hierarchical
• D. Hybrid

Answer: Multilevel

35. Which inheritance type has several classes derived from one base class?

• A. Multilevel
• B. Hierarchical
• C. Multiple
• D. Single

Answer: Hierarchical

36. Which C++ operator allocates memory dynamically?

• A. malloc
• B. new
• C. alloc
• D. create

Answer: new

37. Which C++ operator releases memory allocated with new?

• A. free
• B. delete
• C. remove
• D. release

Answer: delete

38. Which object is used for standard output in C++?

• A. cin
• B. cout
• C. cerr
• D. printf

Answer: cout

39. Which object is used for standard input in C++?

• A. cout
• B. cin
• C. clog
• D. scanf

Answer: cin

40. Which operator is used with cout to send data to output?

• A. >>
• B. <<
• C. ->
• D. ::

Answer: <<

41. Which operator is used with cin to read data?

• A. <<
• B. >>
• C. &&
• D. ::

Answer: >>

42. Which header is required for cin and cout?

• A. stdio.h
• B. iostream
• C. conio.h
• D. stdlib.h

Answer: iostream

43. What does 'using namespace std;' do?

• A. Imports a file
• B. Makes names from the std namespace available without the std:: prefix
• C. Creates a new namespace
• D. Starts the program

Answer: Makes names from the std namespace available without the std:: prefix

44. What is the scope resolution operator in C++?

• A. .
• B. ->
• C. ::
• D. :

Answer: ::

45. What is an inline function?

• A. A function written on one line
• B. A function whose code the compiler may substitute at the call site
• C. A function inside a loop
• D. A private function

Answer: A function whose code the compiler may substitute at the call site

46. Which keyword refers to the current object inside a member function?

• A. self
• B. this
• C. me
• D. current

Answer: this

47. What is a static data member of a class?

• A. A member unique to each object
• B. A member shared by all objects of the class
• C. A constant member
• D. A private member

Answer: A member shared by all objects of the class

48. What is a template in C++?

• A. A design pattern
• B. A way to write generic code that works with any data type
• C. A header file
• D. A class diagram

Answer: A way to write generic code that works with any data type

49. Which keyword introduces a template in C++?

• A. generic
• B. template
• C. typename only
• D. class only

Answer: template

50. Which block is used to handle an exception in C++?

• A. try
• B. catch
• C. throw
• D. final

Answer: catch

51. Which keyword raises an exception in C++?

• A. raise
• B. throw
• C. signal
• D. error

Answer: throw

52. What does STL stand for in C++?

• A. Standard Template Library
• B. System Type Library
• C. Structured Text Language
• D. Static Type Linker

Answer: Standard Template Library

53. Which STL container stores elements in a resizable array?

• A. list
• B. vector
• C. map
• D. set

Answer: vector

54. Which STL container stores unique key-value pairs?

• A. vector
• B. map
• C. stack
• D. queue

Answer: map

55. Which STL container follows Last In First Out order?

• A. queue
• B. stack
• C. vector
• D. deque

Answer: stack

56. Is C++ a purely object-oriented language?

• A. Yes, completely
• B. No — it also supports procedural programming
• C. Only in newer versions
• D. Only with templates

Answer: No — it also supports procedural programming

57. What is data hiding in OOP?

• A. Deleting data
• B. Restricting direct access to an object's internal data
• C. Encrypting data
• D. Compressing data

Answer: Restricting direct access to an object's internal data

58. What is a mutable member in C++?

• A. A member that cannot change
• B. A member that can be modified even in a const object
• C. A static member
• D. A pointer member

Answer: A member that can be modified even in a const object

59. Which comment style does C++ support that C89 did not?

• A. /* */
• B. //
• C. #
• D. <!-- -->

Answer: //

60. What is the size of an empty class object in C++ typically?

• A. 0 bytes
• B. 1 byte
• C. 4 bytes
• D. 8 bytes

Answer: 1 byte

61. Which of these is a valid C++ file extension?

• A. .c
• B. .cpp
• C. .cs
• D. .py

Answer: .cpp