How can you prevent a class from being inherited?

• A. Declare the class as static.
• B. Declare the class as protected.
• C. Declare the class as final.
• D. Declare the class as abstract.

Answer: (C)

Declaring a class as final is the correct approach to prevent the class from being inherited. When a class is marked as final in Java, it indicates that the class cannot be subclassed. This means that no other class can extend the final class, ensuring that its implementation remains unchanged and preventing any derived classes from altering its behavior.

Using the final modifier is crucial when you want to provide a specific implementation that should not be modified or extended. This is helpful for maintaining the integrity of your design, especially in cases where further inheritance could lead to undesirable behaviors or complexity.

In contrast, declaring a class as static applies only to nested classes, where it indicates that the class does not belong to an instance of the enclosing class. This concept does not apply to top-level classes and does not prevent inheritance.

Declaring a class as protected is also insufficient for inheritance prevention, as protected visibility allows subclasses (even in different packages) to inherit from the class while still permitting access to its members.

Lastly, declaring a class as abstract means that the class cannot be instantiated and is intended to be subclassed. Abstract classes are designed for inheritance and provide a base for other classes to build upon, which directly contradicts the goal of preventing inheritance.