问题补充：
What makes us worried is that the number of people to drug is .
A. addicted ; increased
B. addicting; increased
C. addicted ; increasing
D. addicting; increasing
答案：
A. addicted ; increased
B. addicting; increased
(答案→)C. addicted ; increasing
D. addicting; increasing
解析：考查非谓语动词，名词people 和动词addicte是动宾关系，所以用过去分词做后置定语，addicted意思“上瘾”，increased意思“增加”，句子意思“让我们担心的是人沉迷于毒瘾的数量在增加”
