—How long do you think it will bethe Stock Market returns to normal?—At least one year I

问题补充：

—How long do you think it will bethe Stock Market returns to normal?

—At least one year, I guess.

A. when

B. before

C. until

D. that

答案：

A. when

(答案→)B. before

C. until

D. that

解析：多久之后证券市场才能恢复正常？