18. Which of the following groups of numbers are all prime numbers?
A. 7, 17, 29, 49
B.2, 3, 5, 9
C. 2, 5, 15, 19
D. 3, 11, 23, 31

D

Step-by-step explanation:

3,11,23, and 31 can only be divided by 1 without becoming a decimal.

false

step-by-step explanation:

the reason i say this is because for a certain length of sides you can pick any two and the length is wither equal or greater than the third side and in this case it's not.

3 + 5 = 8

8 is smaller than 9 which is the third side.

hope this : )