The primary organs of excretion are the
a. heart and lungs.
b. lungs and kidneys.
c. kidneys and liver.
d. liver and pancreas.

the father in the first generation probably had the recessive colorblind trait in his x chromosome. if he and his wife both had the colorblind trait, even if she had 1 recessive and 1 dominant, then that trait would be passed on to their kids.

(since you didn't attach the family tree this is just an assumption)