The correct answer is Parasitism.Concept:Parasitism is a relationship between two species where the smaller species usually harms its host or takes nutrients from the host.This species is called a "parasite."On the other hand, the species that harbour the parasite is called the host.This process in which the host body is harmed by parasites is called parasitism.Example: a wasp parasitizing a pupa of a housefly. Host- pupa of house fly wasp.ExplanationParasitism-In the above-mentioned question, we can find two organisms belonging to two different species coming together, one species benefiting from the other, and the other species getting harmed.So we can say that this is an example of parasitism.where one species is a parasite and another is the host.Hence, "If two organisms belonging to two different species come together in association and one is harmed and the other is benefitted, such an association is parasitism."Additional InformationSymbiosis:Any two organisms /species(animal or plant)living in close association.Commonly one living in or on the body of the other are considered to be a symbiote.For Example In marine fishes, cleaning symbiosis is commonly observed when neon gobies are cleaned inside the mouths of grouper fish.Mutualism:Mutualism refers to a relationship in which both partners are dependent on each other.In this kind of relationship, both species benefited from each other.Example: In plants, fungi and algae show a mutualistic relationship where the fungi protect the algae. In return, it's gets food from algae.Commensalism:It is a Hetero specific relationship.It is mainly centred around food coaction.In this relationship, one partner benefited from the other But the host did neither harm nor help.For example, bees feed on nectar where nectar is the host.So Symbiosis, Mutualism, and Commensalism are not the correct answer.