Eye colour in humans appears to be controlled by multiple alleles.

 Eye colour in humans appears to be controlled by multiple alleles. The green allele and the brown allele are dominant to blue. Green eye colour is expressed only in the absence of a brown allele.

Red-green colour blindness is a sex-linked trait. Red-green colour blindness (X^rg) is the inability to distinguish between red and green. The (X^rg) allele follows the pattern of recessive inheritance.

Legend: Brown eyes (B), blue eyes (b), Green eyes (G), red-green color blindness (X^rg), and X not colour-blind or normal vision.

A colour-blind male with brown eyes and his green-eyed wife who has normal vision have a daughter who is colour-blind and has blue eyes. What is the genotype of this child?

a. X^rgX^rgGb
b. X^rgX^rgbb
c. X^rgX^rgBb
d. X^rgYbb