A software design pattern used to enhance the functionality of an object at…

Correct answer: Decorator

Explanation: The decorator pattern attaches additional responsibilities to an object dynamically. It provides a flexible alternative to subclassing for extending functionality at run-time without changing the original class.

• How it works: Decorator classes wrap the original object and add behavior before or after delegating requests to the wrapped object.

• Why it fits: It lets you stack or combine decorators at run-time to enhance functionality without modifying the underlying object or creating many subclasses.

• Use case example: To add logging or caching to an object at run-time, create a LoggingDecorator or CachingDecorator that wraps the original object and adds the behavior.

Why the other choices are not the best fit:

• Adapter: Converts one interface to another so incompatible interfaces can work together; its goal is compatibility, not adding new responsibilities.

• Delegation: A technique where an object hands tasks to another object. It is a useful principle but not the specific structural pattern intended for dynamically layering responsibilities.

• Proxy: Acts as a surrogate to control access, add lazy initialization, or perform checks. While it can introduce behavior, its primary intent is access control rather than transparent extension of responsibilities.