An Epistasis Scenario in Labradors

The gene for baldness has 2 alleles, X and x. This gene is epistatic to the gene for fur coat in labradors, which has allele B for black coat fur and allele b for brown coat fur.

A mother labrador has the genotype XxBb and a father labrador has an unknown genotype which is homozygous for the coat fur gene.

Given that 25% of their offspring are bald, which of the following statements must be true?

A) The baldness gene is dominant epistatic to the coat fur gene.

B) 37.5% of their offspring will have black coat fur.

C) The father labrador had a parent with the same phenotype.

D) If the mother labrador has the genotype XXbb instead, there will be more offspring with brown coat fur than black coat fur.