某地区近年来患支气管炎的人逐年增多，其主要原因是_刷题宝

题干

某地区近年来患支气管炎的人逐年增多，其主要原因是（）

A：土壤被污染

B：食物被污染

C：遗传物质改变

D：大气被污染

上一题下一题 0.0难度选择题更新时间:2019-01-13 04:01:54

答案(点此获取答案解析）

D

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