题干

探究“绿叶在光下制造有机物”的实验现象如图,该实验说明(  )

①光合作用需要水;②光合作用需要光;③光合作用需要叶绿体;④光合作用产生淀粉.

A:②

B:②④

C:③④

D:①②④

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答案(点此获取答案解析)

B

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