The right answer for the question that is being asked and shown above is that: "D) symbiotic relationships with algae that photosynthesize and feed them."
These are the following choices:
A) secretions that produce a hard protective skeleton.
B) the inability to leave the reef and swim after prey.
C) stinging cells that kill prey and discourage predators.
D) symbiotic relationships with algae that photosynthesize and feed them.
