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❓ 题目 What is the main purpose of the passage?

A. A) To argue that the keystone species concept is outdated and should be replaced.
B. B) To describe the origin, importance, and criticisms of the keystone species concept.
C. C) To provide a detailed account of Robert Paine's experiments with starfish and mussels.
D. D) To propose a new method for identifying keystone species in ecosystems.

B) To describe the origin, importance, and criticisms of the keystone species concept.