Quiz on Polymorphism and Interfaces

What is polymorphism in object-oriented programming?

• Defining multiple methods with the same name

• Ability of objects to process messages in different ways

• Encapsulation of methods and variables

• Static method overriding

What concept allows different objects to respond to the same method call in their own way?

• Encapsulation

• Polymorphism

• Inheritance

• Overloading

Which of the following demonstrates polymorphism?

• Using multiple constructors in a class

• Overloading a method

• Invoking a subclass-specific method through a superclass reference

• Declaring private fields in a class

Polymorphism supports the design of systems that are:

• Statically linked

• Extensible and flexible

• Dependent on superclass behavior only

• Restricted to single-level inheritance

Which programming feature ensures polymorphism?

• Method overriding

• Abstract methods

• Interfaces

• All of the above

What determines which method implementation is executed in polymorphism?

• Type of variable reference

• Method signature

• Actual object type

• Compiler settings

Abstract methods in a class:

• Must be defined with final

• Are always private

• Do not provide an implementation

• Can include static logic

What keyword is used to declare an abstract class in Java?

• interface

• abstract

• public

• polymorphic

Why can’t abstract classes be instantiated?

• They are static

• They contain unimplemented methods

• They lack constructors

• They must implement Serializable

Which keyword is used to declare an interface?

• class

• interface

• abstract

• public