Genetics: Analysis and Principles 5th Edition by Robert Brooker

Exercise 47

Parental generation: True-breeding flies with red eyes and long wings were crossed to flies with white eyes and miniature wings. All F 1 offspring had red eyes and long wings.The F 1 female flies were then crossed to males with white eyes and miniature wings. The following results were obtained for the F 2 generation:
129 red eyes, long wings
133 white eyes, miniature wings
71 red eyes, miniature wings
67 white eyes, long wings
What is the map distance between these two genes
A) 32.3 mu
B) 34.5 mu
C) 16.2 mu
D) 17.3 mu