1. Assume eight different strains of fly have been isolated, each shows a recessive white eye trait. Crosses are performed as follows; (w) indicates white-eyed progeny, (R) indicates wild-type red eyes.
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2. Based on these crosses, how many different genes are present and what strains have mutations in the same gene as does strain A?
A. 2, B, E, and H
B. 3, B, and C
C. 3, B, E, and H
D. 3, B, C, and H
E. 4, B, and H