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 fruit shape in summer squash. Each gene has two alleles, one of which is dominant for fruit shape. Genotypes of the form A- B- have disc-shaped fruit, those of the form A- bb and aa B- have sphere-shaped fruit, and genotype aa bb has long fruit. What ratio of disc : sphere : long 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