– What place is it?

---Haven’t you found out we ______back where we ______?

A．were; had been

B．are; were

C．were; have been

D．are; had been

按调查对象的范围，常用调查方法分为（）。

A.普查、抽样调查、病例调查

B.普查、典型调查、队列调查

C.普查、抽样调查、案例调查

D.普查、抽样调查、典型调查

E.普查、抽样调查、队列调查