What offspring will be obtained by crossing a hornless homozygous cow (the hornless gene B dominates) with a horned bull

According to the designation introduced in the problem statement, we will write the hornless gene as B, then the gene that determines the development of horns will be b.

A homozygous hornless cow is BB and produces B-type eggs.

To have horns, a bull must be homozygous – bb, because the sign of horniness is recessive according to the condition of the problem and for its implementation it is precisely the homozygous genotype that is required. The sperm produced by it – b.

When crossing the data of a cow and a bull, we will obtain genotypically identical calves BB, which will correspond to the hornlessness.

Correct answer: all bB