Which of the following is a common example of a repetitive action handled by loops?

The correct choice highlights a fundamental use of loops in programming, which is iterating over arrays. When you have an array—a collection of elements—you often need to perform the same action on each element of that array, such as accessing its value, modifying it, or performing calculations. Loops allow you to efficiently execute such repetitive actions without needing to write the same code multiple times.

For example, a common task might involve using a loop to go through an array of numbers, calculating the sum or finding the maximum value. This approach is not only simpler but also makes code cleaner and easier to maintain. The essence of loops is their ability to reduce redundancy, making them critical when dealing with collections of data like arrays.

In contrast, updating variables, defining functions, and writing comments do not inherently involve repetitive actions that benefit from a loop structure. Updating variables can be a one-time action, defining functions generally outlines behavior rather than repetition, and writing comments serves to document code rather than executing it. Thus, iterating over arrays stands out as a classic example of a scenario where loops are essential for repetitive tasks.