In which programming paradigm do encapsulation, inheritance, and polymorphism play a key role?

The key role of encapsulation, inheritance, and polymorphism is fundamentally tied to object-oriented programming. This paradigm focuses on the concept of "objects," which can contain both data and methods.

Encapsulation allows for bundling the data (attributes) and the methods (functions) that operate on the data into a single unit, or object. This not only provides a way to organize code but also restricts direct access to some of the object's components, leading to increased security and reduced complexity.

Inheritance enables a new class to inherit properties and behaviors from an existing class. This fosters code reusability and establishes a hierarchical relationship between classes, making it easier to create and maintain programs.

Polymorphism allows methods to do different things based on the object it is acting upon, enabling a single interface to be used for different actual data types. This adds flexibility and efficiency to code handling.

These concepts are central to building robust, scalable, and maintainable software in object-oriented programming, making it the most suitable choice for a question aimed at identifying these characteristics. Other paradigms like procedural, logic, and declarative programming do not inherently focus on or utilize these principles in the same way that object-oriented programming does.