All the different populations that live together in an area

• A. Estuary
• B. Shark
• C. Temperature
• D. Community

Answer: (D)

The concept here is the community, which is the assemblage of all living populations of different species that coexist and interact in a given area. This includes plants, animals, fungi, and microbes and the relationships between them, such as predation, competition, and mutualism. For example, in a pond the community would include algae, aquatic plants, insects, fish, and microorganisms that all inhabit and influence one another. An estuary is a habitat type, not the term for all living populations there. A shark is just one species, not the whole set of species in the area. Temperature is an abiotic factor describing the nonliving environment, not the living assemblage. So the best term for all the different populations living together in an area is the community.