Question

(安徽省马鞍山市2009届高三第一次教学质量检测) It was reported that as many as 50％of patients do not take medicine
      directed，    has drawn doctors’attention．
  

A．when；it

B．as;what

C．as;which

D．that;and

Answer 1

C

考察状语从句和定语从句，as引导方式状语从句，补全应该为as they are directed。Which引导非限制性定语从句指代前面整个句子且做主语。