Answer:
D. mutualism
Step-by-step explanation:
It is a mutualism because the to species behave in ways that benefit both. The anemones have nematocyst with a paralyzing effect in theirs prey. However clown fish are safe because evolve in harmony with the sea anemones. In this alliance the clown fish defends the anemone too. The anemone has urticant that affects clownfish´s depredator.
In summary the clownfish gain feed (detritus left from the anemone) and protection from predation. And the clown fish protect the anemones from some of their predators.