When Thomas Hunt Morgan Crossed His Red-Eyed F₁ Generation Flies

Multiple Choice

When Thomas Hunt Morgan crossed his red-eyed F₁ generation flies to each other,the F₂ generation included both red- and white-eyed flies.Remarkably,all the white-eyed flies were male.What was the explanation for this result?

A) The gene involved is on the Y chromosome.
B) The gene involved is on the X chromosome.
C) The gene involved is on an autosome,but only in males.
D) Eye color in flies is a multifactorial trait.