Polydactyly, having extra fingers or toes, is an autosomal dominant disorder that occurs in cats as well as in humans. A cat breeder collects information about her cats and makes the pedigree below.

Select the term that best describes the genotype of the cats in the third generation that have polydactyly.
A. heterozygous normal
B. heterozygous polydactyl
C. homozygous recessive normal
D. homozygous dominant polydactyl