What is polymorphism in object-oriented programming?

Polymorphism in object-oriented programming refers to the ability of different classes to be treated as instances of the same class through a common interface. This concept allows objects of various types to be handled as if they are objects of a single type, typically through method overriding or method overloading.

In practical terms, polymorphism enables a function or method to operate on objects of different classes, meaning that you can call the same method on different objects and have it behave appropriately depending on the object type. This capability enhances flexibility and maintainability in code, as it allows for the creation of more generalized and reusable code structures.

For example, if you have a base class called "Animal," and subclasses like "Dog" and "Cat," polymorphism allows you to define a method makeSound() in the Animal class, which can be overridden in both Dog and Cat classes. When you call makeSound() on an Animal reference that holds a Dog object, it will bark, and on a Cat object, it will meow.

The other options presented do not accurately define polymorphism. While APIs can certainly be complex, that characteristic is not bound to polymorphism specifically. Data restrictions relate to encapsulation, which governs access to data members,