Which statement describes Inheritance in object-oriented design?

Which statement describes Inheritance in object-oriented design?

• A. When a subclass gets the variables and methods of a superclass.
• B. When a subclass hides a method by using a different name.
• C. When a class implements an interface.
• D. When two unrelated classes share a common base class.

Answer: (A)

Inheritance lets a subclass automatically gain the variables and methods defined in its superclass, so the subclass can reuse and extend that behavior. This creates an is-a relationship: the subclass is a kind of the superclass. The subclass can use the inherited members directly, add new ones, or override existing ones to customize behavior. The statement describes this transfer of members from superclass to subclass, which is what inheritance is. The other options point to different concepts: hiding a method by renaming it isn’t inheritance; implementing an interface is a separate mechanism for defining a contract; and two unrelated classes sharing a common base class would imply an inheritance link, making them related, so the idea of being unrelated doesn’t fit with inheritance.

Inheritance lets a subclass automatically gain the variables and methods defined in its superclass, so the subclass can reuse and extend that behavior. This creates an is-a relationship: the subclass is a kind of the superclass. The subclass can use the inherited members directly, add new ones, or override existing ones to customize behavior. The statement describes this transfer of members from superclass to subclass, which is what inheritance is. The other options point to different concepts: hiding a method by renaming it isn’t inheritance; implementing an interface is a separate mechanism for defining a contract; and two unrelated classes sharing a common base class would imply an inheritance link, making them related, so the idea of being unrelated doesn’t fit with inheritance.