In OOP, what does abstraction refer to?

Abstraction in object-oriented programming refers to the concept of hiding the complexity of a system while exposing only the necessary parts. This allows developers to focus on high-level operations without needing to understand the intricate details of how those operations are performed. By abstracting away the details, the interaction with complex systems becomes simpler and more intuitive.

For instance, when using a class, you might interact with a simplified public interface without needing to know how specific methods are implemented internally. This not only makes the code more manageable but also enhances modularity, as changes to the internal workings of a class do not affect any code that relies on it, as long as the interface remains consistent.

While the other choices touch on important concepts related to object-oriented programming, they do not encapsulate the fundamental idea of abstraction. Making it clear that abstraction focuses on the necessary parts while concealing complexity solidifies the understanding of why it is a core principle in OOP.