If a Woman Is a Carrier for the Color-Blind Recessive

Multiple Choice

If a woman is a carrier for the color-blind recessive allele and her husband has normal vision, what are their chances that a son will be color-blind?

A) none, because the father is normal
B) 50%, since the mother is only a carrier
C) 100%, because the mother has the gene
D) 25%, because the mother is a hybrid
E) None, since the son will also be just a carrier.