Aced it... I just double checked my work with the answers below...
You can get a few of them just by assuming that one of the choices is correct and figuring the last digit.
41 x 21 = (40 + 1) x (20 + 1) = 800+ 40 + 20 +1.
Only one of the choices ends in 1. Don’t bother doing the sum. And, no, I didn’t need paper and pencil.