How are populations, ecosystems, and communities related?

AA community consists of an ecosystem and its physical environment, and an ecosystem is made up of many different populations of organisms.

BA population consists of a community of organisms and its physical environment, and a community is made up of many different ecosystems.

CAn ecosystem consists of a community of organisms and its physical environment, and a community is made up of many different populations of organisms.

DAn ecosystem consists of a population of organisms and its physical environment, and a community.