Use the information and the Punnett square below to answer the question(s). In guinea pigs, the allele for black fur (B) is dominant. The allele for brown fur (b) is recessive. Two guinea pigs were crossed – the cross is below. Which of the following must be the genotypes of the parents?
a) BB x BB
b) BB x bb
c) bb x bb
d) Bb x Bb