According to statistics, a man is more than twice as likely to die of skin cancer _____ a woman. [ ]

A. than

B. such

C. so

D. as

将药物的粉末，徒手切片或浸出液，取少量置于载玻片上，滴加某种化学试剂，盖上盖玻片，在显微镜下观察反应结果的方法是（）

A.化学定性分析

B.微量升华

C.荧光分析

D.显微化学反应