What is polymorphism in object-oriented programming?

• A. Derive classes from multiple bases
• B. Ability to reuse code across projects
• C. Ability to treat objects of different classes through a common interface
• D. Automate parallel execution

Answer: (C)

Polymorphism is the ability in object-oriented programming to treat objects of different classes through a common interface. You define a shared interface or base class with a method, and each subclass provides its own implementation of that method. When you call the method on a reference typed to the common interface, the runtime automatically invokes the correct version based on the actual object, so different objects can respond appropriately to the same operation. This lets you write generic code that works with any object that adheres to the interface, making it easy to add new types without changing existing logic. The other ideas—multiple inheritance, simply reusing code, or parallel execution—address other concerns and don’t capture the essence of interacting with diverse objects through a single interface.