With Independent Assortment, the Ratio of Phenotypes in the F₂

Multiple Choice

With independent assortment, the ratio of phenotypes in the F₂ generation of a cross between true-breeding strains (AA bb × aa BB) can be described as 9:3:3:1 when A and B are dominant over a and b. To what phenotype do the "3"s in the ratio refer?

A) recessive for both traits
B) dominant for the A trait and recessive for the B trait
C) dominant for one trait and recessive for the other
D) dominant for both traits