How do you determine if a number is prime?

To identify a prime number, it is essential to understand its defining characteristic: a prime number has exactly two distinct positive divisors, which are 1 and the number itself. This definition emphasizes the uniqueness of prime numbers in the realm of natural numbers. For instance, the number 5 is prime because its only divisors are 1 and 5; it cannot be divided evenly by any other numbers.

Additionally, while there are other factors to consider in determining the nature of a number (like being greater than 1), it is the exact pattern of having only two distinct positive divisors that distinctly categorizes a number as prime. Therefore, the criterion outlined in the correct answer provides a clear and specific guideline for recognizing prime numbers in mathematics.