Question

In mice, brown eyes (B) are dominant over blue (b). A homozygous brown-eyed male mouse mates with a blue-eyed female and they have offspring. What are the phenotypes and genotypes of their offspring? What are the genotypes of the parents?

Answer 1

Parents: Homozygous brown-eyed (M) - B B
                                    blued-eye (F)     -  b b    [since blue (b) is recessive then                                                                                      and brown (B) is dominant then
                                                                           in order for the blue gene to
                                                                           show the you need double                                                                                              recessive or the brown
                                                                           gene absent 

Offspring:
So based on the Punnett cross then you realize that all the possible of spring carry the genotype B b and as such the phenotype brown eyes