What defines a prime number?

A prime number is defined as a natural number greater than 1 that has no positive divisors other than 1 and itself. This means that it can only be divided evenly (without leaving a remainder) by 1 and the number itself, which aligns perfectly with the definition provided in the answer choice.

For example, the number 5 is a prime number because its only divisors are 1 and 5. In contrast, composite numbers (like 4 or 6) have additional factors besides 1 and themselves, which means they can be divided evenly by other integers.

The other options do not correctly represent the characteristics of prime numbers. Being divisible by 2 describes an even number, and having at least three factors defines composite numbers instead. Being divisible by any whole number also does not apply, as prime numbers are specifically characterized by having only two factors.