A scavenger eats a diseased, rotting animal. After eating the animal, the scavenger feels sick and nauseated. This feeling of nausea is an — A.
external stimulus telling the scavenger to never eat diseased animals again.
B.
internal stimulus telling the scavenger to get rid of food that is dangerous for it.
C.
external stimulus telling the scavenger to eat only plants in the future.
D.
internal stimulus telling the scavenger to tolerate the sick feelings.