B. Look around, since even a changed ecosystem is still an ecosystem.
Explanation:
Ecosystem refers to the interaction or relationship that exist between living organisms and its surrounding environment. This environment provides habitat, food and other needs to the organisms. If the people in the Midwest determine what kind of natural ecosystem they are in, they have to look around the environment they are living. This environment includes all the plants and animals that survive the change which occurs due to humans intervention.
