单选题
英语六级
2016-11-06
Questions 23 to 25 are based on the recording you have just heard.
A．To show that some species cannot be transplanted easily to new environments.
B．To give an example of rapid population growth that is not followed by decline.
C．To emphasize that species with rapidly growing populations harm ecosystem.
D．To introduce a study on the changing population size of certain species.
参考答案
B
答案解析
暂无解析
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