Which statement is true? O A. The number 23 is prime, but 36 is composite. B. The number 33 is prime, but 42 is composite. OC. The number 21 is prime, but 25 is composite. D. The number 27 is prime, but 39 is composite.​

A. The number 23 is prime, but 36 is composite.

Explanation:

Let's go through the possible answer choices

A) This is true because 23 only has the factors 1 and 23. So that's why 23 is prime. We can say 36 is composite since 2 is a factor, ie 36 = 2*18.B) This is false because 33 is not prime. Note how 33 = 3*11, showing that 3 is a factor of 33.C) Similar to B, the statement "21 is prime" is false. Note how 21 = 3*7.D) Like the other false statements, 27 is not prime because 27 = 3*9.