学历改变命运
24小时客服:4008135555/010-82335555
当前位置:首页 > 笔记串讲 > 自考《英语(二)》试题练习:完成句子题(

自考《英语(二)》试题练习:完成句子题(8.24)

2017年08月24日    来源:自考365   字体:   打印

  单选题

  [完成句子]Heavy metals are persistent; they do not break down to other chemicals in the environment. Industrially polluted sites usually undergo intensive clean-up and rehabilitation because heavy metals are a health concern once they enter the food chain. Some trace metals are alleged to cause cancer and are also known to cause poisoning.

  Industrially contaminated sites usually require a thorough clean-up due to __________.

  A、the persistence of heavy metals

  B、industrially polluted soils

  C、naturally polluted soils

  D、rock and soil chemistry

  
关闭