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❓ 题目 What is the author's main purpose in the passage?

A. To argue that the economic valuation of ecosystem services is universally beneficial
B. To describe the origins and applications of the concept of ecosystem services
C. To present both the advantages and criticisms of the economic valuation of nature
D. To propose a new method for calculating the monetary value of ecosystems

To present both the advantages and criticisms of the economic valuation of nature