In programming, what does the term "nesting" refer to?

Nesting in programming refers to the practice of placing one structure inside another. This concept is applicable to a variety of programming constructs, such as loops, conditional statements, and functions. For example, you might have a loop that contains another loop (known as nested loops), or an if statement that includes another if statement within its block. This allows for complex operations and logic to be executed in a structured manner.

The ability to nest structures enhances the capability of the programming language to handle sophisticated tasks, allowing developers to break down problems into simpler sub-problems and manage them efficiently. Thus, the term "nesting" captures this idea of embedding one thing within another, making the correct answer clear in this context.