OOPs MCQ

Test your knowledge with important OOPs MCQ and their applications. These MCQs are beneficial for competitive exams too. Explore 30 + more OOPs MCQs at Bissoy

• Which one of the following is the right way to invoke a method?
  ক

  $object->methodName();

  খ

  object->methodName();

  গ

  object::methodName();

  ঘ

  $object::methodName();
• Which one of the following is the right way to call a class constant, given that the class is mathFunction?
  ক

  echo PI;

  খ

  echo mathFunction->PI;

  গ

  echo mathFunction::PI;

  ঘ

  echo mathFunction=PI;
• Which one of the following is the right way to define a constant?
  ক

  constant PI = “3.1415”;

  খ

  const $PI = “3.1415”;

  গ

  constant PI = ‘3.1415’;

  ঘ

  const PI = ‘3.1415’;
• Which one of the following can be used to instantiate an object in PHP assuming class name to be Foo?
  ক

  $obj = new $foo;

  খ

  $obj = new foo;

  গ

  $obj = new foo ();

  ঘ

  obj = new foo ();
• Which one of the following property scopes is not supported by PHP?
  ক

  friendly

  খ

  final

  গ

  public

  ঘ

  static
• The practice of creating objects based on predefined classes is often referred to as ______________
  ক

  class creation

  খ

  object creation

  গ

  object instantiation

  ঘ

  class instantiation
• Which of the following term originates from the Greek language that means “having multiple forms,” defines OOP’s ability to redefine, a class’s characteristics?
  ক

  Abstraction

  খ

  Polymorphism

  গ

  Inheritance

  ঘ

  Differential
• The practice of separating the user from the true inner workings of an application through well-known interfaces is known as _________
  ক

  Polymorphism

  খ

  Inheritance

  গ

  Encapsulation

  ঘ

  Abstraction
• Method overriding is combination of inheritance and polymorphism?
  ক

  True

  খ

  false
• What is it called where object has its own lifecycle and child object cannot belong to another parent object?
  ক

  Aggregation

  খ

  Composition

  গ

  Encapsulation

  ঘ

  Association
• What is it called where child object gets killed if parent object is killed?
  ক

  Aggregation

  খ

  Composition

  গ

  Encapsulation

  ঘ

  Association
• What is it called if an object has its own lifecycle and there is no owner?
  ক

  Aggregation

  খ

  Composition

  গ

  Encapsulation

  ঘ

  Association
• Which concept of Java is achieved by combining methods and attribute into a class?
  ক

  Encapsulation

  খ

  Inheritance

  গ

  Polymorphism

  ঘ

  Abstraction
• Which concept of Java is a way of converting real world objects in terms of class?
  ক

  Polymorphism

  খ

  Encapsulation

  গ

  Abstraction

  ঘ

  Inheritance
• When Overloading does not occur?
  ক

  More than one method with same name but different method signature and different number or type of parameters

  খ

  More than one method with same name, same signature but different number of signature

  গ

  More than one method with same name, same signature, same number of parameters but different type

  ঘ

  More than one method with same name, same number of parameters and type but different signature
• When does method overloading is determined?
  ক

  At run time

  খ

  At compile time

  গ

  At coding time

  ঘ

  At execution time
• Which of the following is a type of polymorphism in Java?
  ক

  Compile time polymorphism

  খ

  Execution time polymorphism

  গ

  Multiple polymorphism

  ঘ

  Multilevel polymorphism
• Which of the following is not OOPS concept in Java?
  ক

  Inheritance

  খ

  Encapsulation

  গ

  Polymorphism

  ঘ

  Compilation
• Which of the following is correct about new and malloc? i) new is an operator whereas malloc is a function ii) new calls constructor malloc does not iii) new returns required pointer whereas malloc returns void pointer and needs to be typecast
  ক

  i and ii

  খ

  ii and iii

  গ

  i and iii

  ঘ

  i, ii and iii
• What is the correct syntax of declaring array of pointers of integers of size 10 in C++? ; b) int **arr = new int*; c) int *arr = new int; d) int *arr = new int*;
  ক

  int arr = new int;

  খ

  10

  গ

  10

  ঘ

  10
• What is virtual inheritance?
  ক

  C++ technique to avoid multiple copies of the base class into children/derived class

  খ

  C++ technique to avoid multiple inheritances of classes

  গ

  C++ technique to enhance multiple inheritance

  ঘ

  C++ technique to ensure that a private member of the base class can be accessed somehow
• Which of the following is correct about new and malloc?
  ক

  Both are available in C

  খ

  Pointer object initialization of a class with both new and malloc calls the constructor of that class

  গ

  Pointer object initialization of a class using new involves constructor call whereas using malloc does not involve constructor call

  ঘ

  Pointer object initialization of a class using malloc involves constructor call whereas using new does not involve constructor call
• Which of the following is used to make an abstract class?
  ক

  By using virtual keyword in front of a class declaration

  খ

  By using an abstract keyword in front of a class declaration

  গ

  By declaring a virtual function in a class

  ঘ

  By declaring a pure virtual function in a class
• Which of the following is correct in C++?
  ক

  Classes cannot have protected data members

  খ

  Structures can have member functions

  গ

  Class members are public by default

  ঘ

  Structure members are private by default
• Which members are inherited but are not accessible in any case?
  ক

  Private

  খ

  Public

  গ

  Protected

  ঘ

  Both private and protected
• Which of the following statement is true? I) In Procedural programming languages, all function calls are resolved at compile-time II) In Object Oriented programming languages, all function calls are resolved at compile-time
  ক

  I only

  খ

  II only

  গ

  Both I and II

  ঘ

  Neither I nor II
• What happens if a class does not have a name?
  ক

  It will not have a constructor

  খ

  It will not have a destructor

  গ

  It is not allowed

  ঘ

  It will neither have a constructor or destructor
• Which of the following is not a type of inheritance?
  ক

  Multiple

  খ

  Multilevel

  গ

  Distributive

  ঘ

  Hierarchical
• Which of the following is true? I) All operators in C++ can be overloaded. II) The basic meaning of an operator can be changed.
  ক

  I only

  খ

  II only

  গ

  Both I and II

  ঘ

  Neither I nor II
• Which of the following is a static polymorphism mechanism?
  ক

  Function overloading

  খ

  Operator overloading

  গ

  Templates

  ঘ

  All of the mentioned