As soon as you see an even number, you should know that one of the prime number is 2.
The stem says that x*y*z=42 (this means one of the prime is 2). the other ones are 3 and 7 (prime factors).
From this point you can find others by substitution.
1) x + z = y^2 --> we know x is 2 and other numbers are prime. Other numbers that satisfiy this criteria are 3 and 7. Hence y=3. Suffcnt.
(2) x < y < z ---> we know x =2, and in the lis of 2,3,7, y takes the value 3. Hence suffcnt.
ANS : D
Giving another SHOT