Many students in China are nearsighted. The underlined part means ______. [ ]

A. have poor eyesight

B. look very short

C. have good eyesight

D. wear sunglasses

常用于诱发小鼠产生骨髓瘤细胞的油类制剂有（）

A.石蜡油

B.羊毛脂

C.花生油

D.降植烷

E.羊皮脂