某学校的生物课外小组开展大白菜丰产实验，每棵重约4Kg。请问大白菜增产的物质主要来自（）_刷题宝

题干

某学校的生物课外小组开展大白菜丰产实验，每棵重约4Kg。请问大白菜增产的物质主要来自（）

A：土壤中的无机盐

B：土壤中的有机物

C：空气中的二氧化碳和土壤中的无机盐

D：空气中的氧气和土壤中的有机物

上一题下一题 0.0难度选择题更新时间:2017-05-02 09:02:00

答案(点此获取答案解析）

C

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