Question

which symbiotic interaction involves one organism feeding on or within another organism which is positive for one side of the interaction but negative for the other side? mutualism parasitism competition commensalism

Explanation:

Mutualism is a symbiotic relationship where both organisms benefit. Parasitism is a relationship where one organism (the parasite) benefits at the expense of the other (the host). Competition is when organisms compete for resources. Commensalism is a relationship where one organism benefits and the other is neither helped nor harmed. The description in the question matches parasitism.

Answer:

parasitism