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单选题
A

To transport water to high places.

B

To provide air conditioning.

C

To fertilize the soil.

D

To adjust the soil temperature.


参考答案

参考解析
解析:
[考点]推断题。录音指出,他们把管子插进土壤中,这样冷水就会降低土壤温度,选项D与此句同义替换。
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