It seems that the aged people the H7N9 more easily from the recent cases. A. pick upB. mi

问题补充：

It seems that the aged people the H7N9 more easily from the recent cases.

A. pick up

B. mix up

C. set up

D. use up

答案：

(答案→)A. pick up

B. mix up

C. set up

D. use up

解析：pick up捡起，获得；mix up混淆，调和；set up建立，装配；use up用完，耗尽。句意：根据最近的案例来看，好像老年人更容易感染H7N9病毒。 Pick up还可以表示感染某种疾病的含义，故选A。