1. When creating an object of a subclass, what happens to the members of the superclass?

A. They are not accessible B. They are copied within the subclass object C. They are overridden automatically D. They become private members of the subclass

2. Which of the following statements is TRUE about interfaces in Java?

A. Interfaces can extend classes B. Classes can implement multiple interfaces C. Interfaces are instantiated like classes D. Interfaces can have constructors

3. Which of the following types of inheritance is characterized by a base class being inherited by multiple derived classes?

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

4. How can multiple inheritance be achieved in Java?

A. By inheriting multiple classes directly B. By implementing multiple interfaces in a single class C. By extending multiple interfaces D. By creating multiple objects

5. What does the 'implements' keyword signify in Java?

A. A class inherits another class B. A class inherits the properties of an interface C. An interface extends multiple classes D. A class inherits multiple classes directly

6. Which of the following is a correct statement about hybrid inheritance in Java?

A. Java supports hybrid inheritance using classes only B. Hybrid inheritance is supported using interfaces C. Hybrid inheritance is fully supported in Java through classes D. Hybrid inheritance is illegal in Java and cannot be emulated

7. What does the 'instanceof' operator check in Java?

A. Whether an object is null B. Whether a variable is initialized C. Whether an object belongs to a specific class or inherits from it D. The size of an object in memory

8. Which of the following indicates a HAS-A relationship in Java?

A. class Car extends Vehicle B. class Vehicle contains Speed as an attribute C. class Animal implements Mammal D. class Dog extends Mammal

9. What keyword is used in Java to inherit the properties of a base class into a derived class?

A. implements B. inherits C. extends D. imports

10. A class in Java can implement multiple interfaces. What benefit does this provide?

A. It allows multiple constructors in a class B. It enables multiple inheritance of type, avoiding the issues of multiple inheritance with classes C. It restricts access to private members D. It enables the class to inherit private variables from multiple classes

11. How does Java achieve reusability in code using inheritance?

A. By duplicating codes in subclasses B. By extending the functionalities of base classes C. By restricting inheritance to interfaces only D. By avoiding method overriding

12. What is method overriding primarily used for in inheritance?

A. To change the method signature in subclass B. To provide a new implementation of a method inherited from superclass C. To remove a method from subclass D. To duplicate methods without changes

13. The following is true regarding private members in Java inheritance:

A. Private members are inherited but cannot be accessed directly in subclass B. Private members are not inherited at all C. Private members can be accessed directly by subclass using `super` D. Private members can be made public in subclass by default

14. What does the HAS-A relationship imply?

A. Inheritance between classes B. Usage or containment of one class by another C. Implementation of interfaces D. Abstract class extension

15. The "super" keyword cannot be used to:

A. Call superclass method B. Access superclass variable C. Call superclass constructor D. Access private variables of superclass

16. How do interfaces differ from classes regarding inheritance in Java?

A. Interfaces can be extended by classes using the extends keyword B. Classes can implement multiple interfaces but cannot extend multiple classes C. Interfaces cannot be implemented by classes D. Classes must extend interfaces to inherit methods

17. What keyword is used in Java to inherit properties from one class to another?

A. implements B. inherits C. extends D. imports

18. Why does Java not support multiple inheritance with classes?

A. To avoid code duplication B. To prevent ambiguity and complexity in inheritance C. Because Java does not allow inheritance D. Because interfaces are not supported in Java

19. Which concept does inheritance help implement among the following in OOP?

A. Polymorphism via method overriding B. Encapsulation by hiding data C. Overloading of methods D. Abstraction without interfaces

20. Which of the following about the 'super' keyword is NOT true?

A. It helps differentiate variables/methods of superclass from subclass B. It can be used to invoke a superclass’s constructor C. It can be used to access private members of superclass directly D. It is similar to the 'this' keyword but refers to superclass

21. What is the primary purpose of inheritance in Java?

A. To increase the number of classes B. To reuse existing code and extend functionalities C. To restrict access to superclass members D. To reduce the number of methods in a class

22. What is illegal in Java inheritance?

A. A class extending one superclass B. A class extending multiple superclasses C. A class implementing multiple interfaces D. A class extending and implementing interfaces together

23. In Java, what does "single inheritance" imply?

A. One base class has multiple derived classes B. A class inherits from more than one class C. One derived class inherits from one base class only D. Multiple interfaces inheritance

24. When using a superclass reference variable to refer to a subclass object, what members can be accessed using that reference?

A. Only members declared in the subclass B. Only members declared in the superclass C. All members declared in both superclass and subclass D. Neither superclass nor subclass members

25. If a subclass does not define its own constructor, which constructor is used when an object is instantiated?

A. There is a compilation error B. Superclass’s parameterized constructor C. Superclass’s no-argument (default) constructor D. Subclass’s default constructor automatically generated

26. In Java, what relationship does the "HAS-A" relationship describe?

A. Inheritance between classes B. Usage or composition between classes C. Implementation of interfaces D. Method overriding

27. In hierarchical inheritance in Java, how many base classes and derived classes are involved?

A. Multiple base classes and one derived class B. One base class and multiple derived classes C. One base class and one derived class D. Multiple base classes and multiple derived classes

28. Given the class declaration `class Dog extends Mammal`, which of the following is correct?

A. Dog inherits all public and private members of Mammal B. Dog inherits public and protected members but not private members of Mammal C. Dog cannot override methods from Mammal D. Dog can extend multiple classes besides Mammal

29. In Java, which of the following is true about constructors in inheritance?

A. Subclasses automatically inherit constructors from superclasses B. Constructors cannot be inherited but can be called using 'super' C. Constructors from superclasses override subclass constructors D. Constructors do not participate in inheritance

30. What does the 'super()' keyword in Java do?

A. Initializes a new object B. Refers to parent class’s constructor or method C. Refers to current class’s constructor D. Creates a copy of an object

31. What will happen if a subclass and superclass both have a method with the same signature, and the subclass's method is called on a subclass object?

A. The superclass method will always execute B. The subclass method will override the superclass method C. Both methods will execute sequentially D. Compile-time error will occur

32. What is the relationship called when a subclass is a type of its superclass?

A. Has-A relationship B. Uses-A relationship C. Is-A relationship D. Can-A relationship

33. Which of the following shows an example of Java Hierarchical Inheritance?

A. One base class; one derived class B. One base class; multiple derived classes C. Multiple base classes; one derived class D. No inheritance at all

34. Which of the following declarations is illegal in Java?

A. class A extends B {} B. class C implements X {} C. class D extends A, B {} D. class E extends F implements G, H {}

35. Inheritance where a class inherits from another, which in turn is inherited by another class, is called:

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

36. Why is multiple inheritance avoided in Java with classes?

A. It increases code size unnecessarily B. It creates ambiguity due to multiple superclasses having the same methods or fields C. Java does not allow more than one method in a class D. Multiple inheritance is supported in Java without problems

37. What does the 'super' keyword in Java allow a subclass to do?

A. Implement multiple interfaces B. Access methods and variables of the subclass only C. Access methods and variables of the superclass D. Define private methods in the superclass

38. Which statement is true about the instanceof operator in Java?

A. It checks whether a method exists in an object B. It checks if an object is an instance of a specified class or interface C. It casts the object to another class D. It creates a new instance of a class

39. Which constructor is automatically acquired by a subclass in Java?

A. Parameterized constructor of the superclass B. Default constructor of the superclass C. Both default and parameterized constructor of superclass D. No constructor from the superclass is acquired automatically

40. What will be printed if `obj1.printOne()` is called where obj1 is an instance of class Two which extends One with method `printOne()` in class One?

A. Error because printOne() is not inherited B. Output of printOne() in class One C. Output of printOne() in class Two D. Nothing is printed

41. What is NOT a feature of inheritance in Java?

A. Code reusability B. Extensibility of features C. Multiple inheritance through classes D. Achieving abstraction via inheritance

42. How is method overriding achieved in Java inheritance?

A. By defining a method with the same name and signature in the subclass as the superclass B. By creating a new method with a different name in subclass C. By defining static methods in subclass D. By using the 'overload' keyword

43. Java supports which inheritance type(s)?

A. Single, Multilevel, Hierarchical B. Multiple and Hybrid C. Multiple only D. None of the above

44. What will happen if a subclass and superclass both have a method with the same name and signature?

A. Only superclass method will be called B. Only subclass method will be called due to overriding C. Both methods are called simultaneously D. Java throws a compilation error

45. In Java, which keyword differentiates a subclass variable or method from a superclass variable or method when both have the same name?

A. this B. super C. base D. parent

46. If class Dog extends Mammal and Mammal implements Animal, which of the following is true?

A. Dog IS-A Animal B. Dog HAS-A Animal C. Dog cannot be considered an Animal D. Dog only extends Mammal, not Animal

47. In multilevel inheritance, which statement is true?

A. There are multiple base classes at the same level B. A base class is inherited by a derived class which itself is inherited by another derived class C. One class implements multiple interfaces directly D. Multiple classes share the same superclass directly

48. Which class is called the superclass in Java inheritance?

A. The class that inherits properties B. The class that is inherited from C. The class that does not have any methods D. The class with only private members

49. Which of the following best describes single inheritance in Java?

A. One class inherits from multiple classes B. One base class is inherited by multiple derived classes C. One base class is inherited by one derived class D. One class implements multiple interfaces

50. Which of the following statements about the 'instanceof' keyword is correct?

A. It checks if a class inherits from a specific interface only B. It determines if an object is an instance of a particular class or its subclass C. It checks if a class has implemented a method from an interface D. It creates a new instance of a class at runtime