Java Objects Quiz

Which of the following is true about classes in Java?

• A. A class is a blueprint for an object

• B. A class can have multiple instances

• C. A class can inherit properties and methods from another class

• D. All of the above

What is encapsulation in Java?

• A. It is a mechanism to restrict access to class members

• B. It is a way to create multiple instances of a class

• C. It is a technique to achieve polymorphism

• D. It is a process of hiding data within a class

Which of the following is an example of polymorphism in Java?

• A. Method overloading

• B. Method overriding

• C. Both A and B

• D. None of the above

What is abstraction in Java?

• A. It is a way to create multiple instances of a class

• B. It is a technique to achieve polymorphism

• C. It is a process of hiding data within a class

• D. It is a mechanism to represent essential features without including the background details

Which keyword is used to create an object in Java?

• A. new

• B. create

• C. object

• D. instance

What is the purpose of a constructor in Java?

• A. To create multiple instances of a class

• B. To initialize the object's state

• C. To achieve polymorphism

• D. To hide data within a class

Which of the following is NOT a valid access modifier in Java?

• A. public

• B. private

• C. protected

• D. global

What is the output of the following code? public class MyClass { public static void main(String[] args) { MyClass obj = new MyClass(); System.out.println(obj); } }

• A. MyClass@

• B. MyClass

• C. obj

• D. null