Which of the following best represents the view of ecological communities associated with

Which of the following best represents the view of ecological communities associated with Frederick Clements in paragraph 2？

A．Only when all species in a community are at the reproductive stage of development is an ecological community precisely balanced.

B．When an ecological community achieves "climatic climax," it begins to decline.

C．All climates have similar climax communities.

D．Ecological communities eventually reach the maximum level of balance that is possible for their region.

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