Answer:
A. Commensalism because the flatworm benefits while the horseshoe crab doesn't but isn't affected.
B. Predator-prey since the shark is the predator and the seal is the prey.
C. Competition because the two males are fighting for the female.
Hope this helps :)
I think none of the men are the father, they don’t match the child’s results.
They are the endocrine glands
