Which of the Following Is an Example of an Ecosystem

Multiple Choice

Which of the following is an example of an ecosystem?

A) All of the brook trout in a 500 hectare² river drainage system.
B) The plants, animals, and decomposers that inhabit an alpine meadow.
C) A pond and all of the plant and animal species that live in it.
D) The intricate interactions of the various plant and animal species on a savanna during a drought.
E) Interactions between all of the organisms and their physical environment in a tropical rain forest.