The USA is a large country in many different dialects are spoken.A. that　B. whichC. wher

问题补充：

The USA is a large country in many different dialects are spoken.

A. that

B. which

C. where

D. it

答案：

A. that

(答案→)B. which

C. where

D. it

解析：本题修饰名词表示的是一个地点，在介词in需用关系词which，故本题选B。