Java Inheritance MCQs

Question 1

What is the difference between an interface and an abstract class regarding multiple inheritance in Java?

Accepted Answer

A class can implement multiple interfaces but can only extend one class, including abstract classes

Answer

A class can extend multiple abstract classes but only implement one interface

Answer

Neither interfaces nor abstract classes support any form of multiple inheritance

Answer

A class must implement every interface in the program

Question 2

What does the Java keyword 'protected' control?

Accepted Answer

It allows access to a member from within its own class, subclasses, and other classes in the same package

Answer

It makes a variable completely inaccessible from any other class

Answer

It allows access from any class in any package without restriction

Answer

It marks a method so it cannot be overridden

Question 3

What is the purpose of the Java 'Object' class?

Accepted Answer

It is the root class from which every other class in Java implicitly inherits

Answer

It is an interface that must be manually implemented by every class

Answer

It only exists for backward compatibility and is rarely used

Answer

It stores the compiled bytecode of a program

Question 4

Which keyword is used by a class to inherit from another class in Java?

Accepted Answer

extends

Answer

implements

Answer

inherits

Answer

super

Question 5

Which of the following keywords is used to inherit a class in Java?

Accepted Answer

extends

Answer

implements

Answer

inherits

Answer

super

Question 6

Why does Java NOT support multiple inheritance through classes?

Accepted Answer

To prevent ambiguity issues such as the Diamond Problem

Answer

Because classes cannot have more than one constructor

Answer

To reduce the bytecode file size of compiled classes

Answer

Because the JVM stack cannot hold multiple parent references

Question 7

Can a Java class directly inherit multiple classes using the extends keyword?

Accepted Answer

No, Java does not support multiple class inheritance

Answer

Yes, separated by commas

Answer

Yes, if all parent classes are abstract

Answer

Only in Java 17 and later

Question 8

Which of the following members of a superclass are NEVER inherited by a subclass?

Accepted Answer

Constructors

Answer

Public methods

Answer

Protected fields

Answer

Package-private methods in the same package

Question 9

What happens if a superclass method is declared as final?

Accepted Answer

It cannot be overridden in a subclass

Answer

It cannot be inherited by a subclass

Answer

It can only be called once in the entire program

Answer

It must be declared as static

Question 10

In constructor chaining, which statement is true regarding the super() call in a subclass constructor?

Accepted Answer

It must be the first statement in the constructor

Answer

It must be placed at the end of the constructor

Answer

It can only be used with static methods

Answer

It is only allowed in abstract classes

Core Java Fundamentals Quiz

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Inheritance MCQ Questions