Which of the following sets contains only prime numbers?

The set that contains only prime numbers is the one that includes 2, 3, 5, and 7. These numbers are classified as prime because each of them has exactly two distinct positive divisors: 1 and the number itself. For example, the number 2 can only be divided evenly by 1 and 2, and similarly for 3 (which is divisible by 1 and 3), 5 (divisible by 1 and 5), and 7 (divisible by 1 and 7).

In contrast, the other sets contain numbers that do not meet the criteria for being prime. For instance, 1 is not considered prime by definition, as it only has one positive divisor. The numbers 4, 6, 8, and 10 are even numbers greater than 2, making them composite since they can all be divided by 2, thus having more than two unique divisors. These distinctions help clarify why the selected set is the only one that exclusively contains prime numbers.