Hi i wanted to help you but i hate math do i am soooooooo sorry
Pick 1: 6 yellow out of 15 total marbles = 6/15 = 2/5
Pick 2: 6 yellow out of 15 total marbles = 6/15 = 2/5
Pick 1 AND Pick 2
2/5 x 2/5 = 4/25
It shoukd be A if im not mistaken
-3 is your the answer a negitive times a negitive is a positive
happy to help