Which characteristic defines composite numbers?

Composite numbers are defined as whole numbers that have more than two distinct factors. This means that a composite number can be divided evenly by numbers other than just one and itself. For instance, the number 6 is a composite number because it can be divided evenly not only by 1 and 6, but also by 2 and 3.

In contrast, the characteristic stating that a number has exactly two factors describes prime numbers, which cannot be composite. The condition of being a whole number greater than one is true for all composite numbers, but it is also true for prime numbers, which limits its usefulness in distinguishing composite numbers specifically. The statement about numbers that cannot be divided evenly by one does not accurately reflect composite numbers, as all whole numbers, including composite numbers, can be divided by one evenly.

Therefore, the identifying feature of composite numbers is that they possess three or more factors, confirming choice C as the correct definition.