A feeding relationship in which both organisms benefit is referred to as

Explanation

Commensalism is a feeding relationship where one of the species benefits, while the other is unaffected but doesn't benefit. In parasitism, one of the organisms benefits at the expense of the other, thereby causing harm on the second(host). Predation involves one organism killing and feeding on the other organism. Saprophytism is a mode of nutrition whereby an organism feeds on a dead organism. None of these matches the description given above in the question.

Symbiosis even though it is a terminology that generally defines the different types of feeding relationships that exist among organisms, it can also be said to be  a close relationship between two species in which usually both get benefits from each other. Thus, Option E is the best and correct answer.