The diagram shows a sponge. What is the function of the structures labeled X?

providing protection from predators
fertilizing eggs
filtering and digesting food
stinging prey

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)