Answer:
Option (4).
Step-by-step explanation:
Biological interactions are important among the organism that helps them to survive in their environment. Biological interactions may be harmful or useful for the organisms.
Mutualism may be defined as a type of interaction in which both the species are benefited from each other. Amy should include relationship A in mutualism. Commensalism may be defined as the type of interaction in which one species is benefited and other organism is neither benefited nor harmed the individual. The relationship B is involved in commensalism.
Thus, the correct answer is option (4).