Which of the Following Scenarios Describes an Example of Epistasis

Multiple Choice

Which of the following scenarios describes an example of epistasis?

A) Albino corn snake result from animals having recessive genotypes for each of two genes.
B) In many mammals one genotype (ee) prevents any fur color from developing.
C) In fruit flies white eyes can be due alleles of a gene on the X chromosome or a combination of other genes.
D) In cacti, there several genes control the type of spines.