The correct option is this: A DAUGHTER WILL NOT BE COLOR BLIND BECAUSE THE FATHER IS NOT A CARRIER OF THE RECESSIVE ALLELE.
A trait is said to be sex-linked when it is carried on the chromosomes. The female chromosome is made up of XX while the male chromosomes is made up of XY, thus, in the question given above, the color blind trait is found on the woman's chromosomes. Since their first child is a boy and is color blind, it means that he got the trait from the woman, because she was the one who donated the X chromosomes that is defective. For this couple, half of all the male children that they give birth to will have normal vision while the other half will be colour blind. Because, the father's X chromosome is normal, all the girls that this couple give birth to will have normal vision but they will carry the colour blind trait in their chromosomes.
