When Thomas Hunt Morgan crossed red-eyed F1 generation flies to each other, the F2 generation included both red- and white-eyed flies, but all the white-eyed flies were male. Which of these best explains Morgan's result?
A) The gene involved is located on the Y chromosome. B) The gene involved is located on the X chromosome. C) The gene involved is located on an autosome, but only in males. D) Other male-specific factors influence eye color in flies.