Dihybrid crosses can be conducted with two organisms that are heterozygous for two different traits: SsYy x SsYy for example. Which genotypic ratio shows that genes in dihybrid crosses are inherited according to the principle of independent assortment?

A.
25:25:25:25

B.
50:50

C.
3:1

D.
9:3:3:1

D. 9:3:3:1

This genotypic ratio shows that genes in dihybrid crosses are inherited according to the principle of independent assortment, where the alleles of each gene segregate independently of the alleles of the other gene.