要验证Zn、Fe、Cu三种金属的活动性顺序，可选用的一组试剂是（　　）

A．Fe、Cu、Zn（NO₃）₂溶液

B．Cu、FeCl₂溶液、ZnCl₂溶液

C．Zn、FeSO₄溶液、CuSO₄溶液

D．Fe、CuSO₄溶液、ZnSO₄溶液

Eating Dangshen and Huangqi _________ good for people if they are weak and tired. [ ]

A. is

B. are

C. were

D. was