What is a subclass in object-oriented programming?

A subclass in object-oriented programming refers to a more specific category within a class that inherits attributes and behaviors (methods) from its parent class, also known as the superclass. This relationship allows subclasses to extend or modify the functionality of the parent class, thereby promoting code reuse and establishing a clear hierarchy.

In object-oriented design, the use of subclasses supports the principle of specialization, where a subclass can have additional or overridden methods and properties that are unique to that specific category. For instance, if the base class is "Vehicle," the subclasses could be "Car" and "Truck," each inheriting characteristics like "wheels" and "engine," but also possessing unique features such as "cargo capacity" for trucks or "number of doors" for cars. This specialization helps in organizing code logically and efficiently, making it easier to manage and understanding in larger systems.

The other options do not accurately describe a subclass's functionality within object-oriented programming. An independent object that cannot inherit does not fit the definition of a subclass, which inherently relies on the inheritance mechanism. A more general category aligns with the concept of a superclass rather than a subclass, and a function related to object behavior refers to methods rather than the class structure itself.