Which concept refers to the ability of code to be reused across different programs?

• A. Inheritance
• B. Polymorphism
• C. Encapsulation
• D. Abstraction

Answer: (A)

The concept that refers to the ability of code to be reused across different programs is inheritance. In object-oriented programming, inheritance allows a new class to inherit properties and behaviors (methods) from an existing class. This means that if a base class is designed with certain functionalities, a derived class can reuse and extend those features without having to rewrite the code. This capability not only promotes code reuse but also enhances maintainability and reduces redundancy in programming.

For instance, if you have a base class called "Animal" with common methods like "eat" or "sleep," you can create subclasses such as "Dog" and "Cat" that inherit these methods. This structure enables you to call these methods on instances of "Dog" and "Cat" without duplicating the code contained in "Animal."

The other concepts, while important in their own right within object-oriented programming, do not primarily focus on code reuse across different programs. Polymorphism allows objects to be treated as instances of their parent class, thus offering flexibility. Encapsulation secures the internal state of an object and restricts direct access to some of its components, focusing more on data protection. Abstraction simplifies complex reality by modeling classes based on essential properties, fostering a clearer understanding but not specifically