Which programming approach promotes code reusability?

The choice of modularity as the programming approach that promotes code reusability is fundamentally tied to its design structure. Modularity involves breaking down a program into smaller, self-contained units or modules, each responsible for a specific piece of functionality. This design allows these modules to be developed, tested, and maintained independently.

When a module is created, it can be reused across various programs or different parts of the same program without needing to rewrite the code. This reusability not only saves time and effort but also helps maintain consistency across the software. If a common functionality is needed in multiple places, using a modular approach ensures that any updates or fixes to that functionality only need to be made in one location, further enhancing the efficiency and reliability of the application.

In contrast, recursion, input validation, and hardcoding do not inherently promote code reusability in the same way that modularity does. Recursion is a technique used to solve problems by having a function call itself, which can be powerful but doesn't foster reusable code by itself. Input validation is crucial for ensuring data integrity but does not specifically offer a reuse mechanism. Hardcoding deals with embedding fixed data directly into the code, which makes the code less flexible and reusable, as changes would require