Polyp animals that form coral reefs have many unique adaptations for survival. one polyp feature that is detrimental rather than beneficial is

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.