is known to all that the Amber Room belongs to the Russians.A. AsB. WhichC. ItD. What

问题补充：

is known to all that the Amber Room belongs to the Russians.

A. As

B. Which

C. It

D. What

答案：

A. As

B. Which

(答案→)C. It

D. What

解析：此题重点考查it is known to all和as is known to all的区别，两者都表示众所周知的意思。前者常跟that从句，后者常做状语。