In Genetics, the Dash Symbol (-) Is a "Wild Card

Multiple Choice

In genetics, the dash symbol (-) is a "wild card" that stands for either the dominant allele or the recessive allele; for example, A- means the individual has either the genotype AA or Aa. Two genes that undergo independent assortment affect coat color in Duroc pigs. Each gene has two alleles, one of which is dominant for coat color. Genotypes of the form A- B- are red, those of the form A- bb and aa B- are sandy, and genotype aa bb is white. What ratio of red : sandy : white is expected from the cross Aa Bb × Aa Bb?

A) 10:3:3
B) 9:3:4
C) 12:3:1
D) 9:6:1