Answer:
I think the answer is B. I think energy decreases as it moves up tropic levels when it is lost as the organisms from one level consume the organisms in the other.
Explanation:
It can't be A because animals do travel from one ecosystem to another. It's migration. It's not C because air can be used by organisms as once as the air moves out of their ecosystem because air is everywhere and the organisms need air to breathe and to live. D is definitely incorrect because matter can't be created or destroyed. Remember that an ecosystem is the organisms physical environment. I hope this answers your question.
