The mayor of Beijing says that all construction work for the Beijing Olympics by .A.

问题补充：

The mayor of Beijing says that all construction work for the Beijing Olympics by .

A. has been completed

B. has completed

C. will have been completed

D. will have completed

答案：

A. has been completed

B. has completed

(答案→)C. will have been completed

D. will have completed

解析：句意：北京市市长说所有北京奥林区克建筑将于完成。此题考查英语动词的语态和时态，很显然本题应该用被动语态，因此排除B、D根据时间状语by，应选择将来完成时，因此选C。