Final answer:
The genotype that exhibits a white eye phenotype in Drosophila melanogaster is c) XwXw, which represents a female fly with two copies of the recessive white-eye allele.
The correct option is c) XwXw
Step-by-step explanation:
In Drosophila melanogaster, the wild-type eye color is red, which is dominant over the white-eye mutation. Genotype determines the eye color phenotype in these flies. Since white eyes is a recessive mutation and males are hemizygous (having only one X chromosome), they display white eyes if they have the recessive allele on their single X chromosome. The genotypes that will exhibit a white eye phenotype in Drosophila are XWXW (homozygous white female), XWY (white-eyed male), and XwXw (homozygous white female).
where the female fly has two copies of the white-eye allele. Other genotypes like XWXW and XwY would lead to red eye phenotype because they either have a dominant red-eye allele or, in the case of males, only a single copy of the white-eye allele is not sufficient for white eyes to be expressed due to their hemizygosity.
The correct option for a genotype with a white eye phenotype is c) XwXw