Suppose that a mouse with black fur has both an allele for black fur and an allele for white fur (Bb). Based on this information, you can conclude that the dominant allele must be for fur andthe recessive allele must be for fur.

On the basis of the given information, the dominant allele must be for black fur and the recessive allele must be for white fur.

Explanation:

A variation of a gene, which will generate a certain phenotype, even in the existence of other alleles is known as a dominant allele. On the other hand, a version of a gene that needs to be homozygous when inherited in order to be articulated in the phenotype is known as a recessive allele. The offspring will not express the phenotype of the recessive allele if it is inherited together with a dominant allele, that is, the phenotype of the dominant allele will just be expressed.

The dominant must be for the black fur and the recessive must be for the white fur.