Parasites benefit their hosts is the true statement. Parasitism is a symbiotic relationship in which one organism (the parasite) benefits from another organism and this other organism is harmed by the parasite. The others aren't true because: - the organism that is harmed doesn'y adapt and evolve it still is vulnerable - it is a fact that parasites change from hosts - phoresy is an association between two species in which one transports the other. This does not include killing the host (is possible, but it is not a condition under which you can call something a phoresy).
Answer: Parasitism causes both the parasite and host to adapt and evolve.
Explanation:
A parasitism is a kind of symbiotic relationship in which two species lives in close association. In this association one species is benefited by harming the other species so as to derive nourishment and shelter. The species which causes harm is called as the parasite the species which is being harmed is called as host.
In parasitism the parasitic as well as the host species evolve together. The parasite is adapted to live in the host body in adverse conditions too. Also the host is adapted to get rid from the parasite and attain a protection from the parasitic damage. Some host build symbiotic mutualistic association with other species to get rid from parasites. The Ladybugs live on the plants, eating the aphids and benefiting by obtaining food, on the other hand the plants are getting rid of aphids (parasites).
