—Oh this is really an old building.—Do you know when it ?A. has builtB. is builtC. was bu

问题补充：

—Oh, this is really an old building.

—Do you know when it ?

A. has built

B. is built

C. was built

D. will be built

答案：

A. has built

B. is built

(答案→)C. was built

D. will be built

解析：句意：哦，这真的是一个古老的建筑。你知道它是什么时候建的吗？was built一般过去时的被动语态表示过去被建，故选C