Answer:
2 only
Explanation:
Only even PRIME number is 2.
Why do we need EVEN PRIME numbers?
Say we do 11*5 we get 55 but when we add one we get 56
Meaning: An odd number multiplied by an odd number plus an odd number equals EVEN number which isn't PRIME. 2 being the ONLY even prime is therefore the only number we can choose.