----- I’m going to the States. ----- How long you in the States?A. are; stayed B. are;

问题补充：

----- I’m going to the States.

----- How long you in the States?

A. are; stayed

B. are; staying

C. have; stayed

D. did; stay

答案：

A. are; stayed

(答案→)B. are; staying

C. have; stayed

D. did; stay

解析：现在进行时态表示将来。