填空题

A. our share of resources
B. a biological creature
C. a given area
D. the maintenance of the ecosystem
E. the source of food
F. various species
In an ecosystem, plants, animals and humans live together in （）.

【参考答案】

C

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A. our share of resources B. a biological creature C. a given area D. the maintenance of the ecosystem E. the source of food F. various species In an ecosystem, plants, animals and humans live together in （）.

A. our share of resources
B. a biological creature
C. a given area
D. the maintenance of the ecosystem
E. the source of food
F. various species
In an ecosystem, plants, animals and humans live together in （）.