Concept:A group of different species living together and interacting in one habitat is called a community.Explanation:Different species sharing the same habitat and interacting with each other form a community.This includes relationships like competition, predation, and mutualism among the species.A population includes only members of the same species, while a niche is the role of a species.The biosphere is the global sum of all ecosystems.Thus, the correct ecological term is community.Answer:A. community