Association between sea anemone and clownfish is that of:
Amensalism
A clownfish is immune to the sting of the sea anemone and therefore lives in a sea anemone home. By this association, the clownfish is protected from predators that keep away from the stinging cells of the sea anemone and the sea anemone is unaffected. Therefore this relationship is beneficial to one organism and does not affect the other organism, such a relationship is called commensalism. Parasitism is a relationship where one organism uses another organism as host, thus obtaining food, protection and other resources from the host. This relationship is beneficial to the parasite but harmful to the host. Ammensalism is a relationship where one organism is harmed by the relationship, while the other is unaffected. Aposematism is not a relationship, it is an antipredatory mechanism, where organisms display warning signals to indicate its unpalatability.