An Ecologist Might Define a Soil Ecosystem as All the Organisms

Multiple Choice

An ecologist might define a soil ecosystem as all the organisms and interactions involved in transferring nitrogen through the system.He might also define a soil ecosystem as the flow of energy through all the organisms in 2 square meters of soil.Why would both definitions be correct?

A) Both include all organisms in the system.
B) Both define subsets of the system that are appropriate for study.
C) Both consider movement of energy but not nutrients.
D) Both include the most important components of the system.
E) Both follow the flow of energy through the system.