Question 8 Proteins encoded by genes A, B, C, and D control the production of a black pigment. Alleles a, b, , and d code for nonfunctional proteins. Ablack AA BB CC DD is crossed with a colorless aa bb cc dd to give black F1. The F1 is then backcrossed with a colorless aa bb cc dd. Genes A, B, and D independently assort, but genes A and C are linked with a 10 m.u. separation. A, B, C, and D act in a pathway as follows: A B C colorless colorless grey brown black O What percentage of the F2 are grey? O 1/8 O 1/20 O 1/40 O 9/40 O 1/80 O 9/80