Answer:
a. The observed frequencies (91 black, 39 yellow, and 30 chocolate) are similar to the expected values for a dihybrid cross, which has a phenotype ratio of 9:3:3:1 Â
b. Coat color is a trait characterized by the presence of melanin, thereby genes that encodes for enzymes involved in the biosynthesis of melanin are expected to be involved in the expression of this trait