Answer: Possible gametes: YS, Ys, yS, or ys
Explanation: When given the genotype of a dihybrid to cross, you have to account for all possibilities. A way to do this would be to think of it like you’re multiplying or FOIL-ing an equation in math. This means YySs could also be written as: (Yy) x (Ss). Simply multiple the first variable of the first group (Y) by the first and second variable of the second group (S and then s), and then repeat for the second variable of the first group (y).