What does a loop require to stop repeating?

A loop requires a specific condition to be met in order to stop repeating. This condition, often referred to as a loop termination condition, is a fundamental aspect of loop control structures in programming. When the loop is executed, it continues to iterate until this condition evaluates to false.

For example, in a while loop, the loop continues as long as the specified condition is true. Once that condition becomes false, the loop terminates, and control is transferred to the next statement following the loop. Similarly, in a for loop, the loop runs for a predetermined number of iterations based on the initialization, condition, and increment or decrement expressions. The condition associated with the loop acts as a critical check that determines when the loop should finish executing.

While user input, return statements, or variable changes can influence the behavior of a loop, they are not the essential requirement that explicitly defines the stopping criterion of a loop. The specific condition serves as the definitive trigger that dictates whether the loop will continue or stop, thereby making it the correct answer.