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

问题补充：

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

A. As

B. Which

C. It

D. What

答案：

(答案→)A. As

B. Which

C. It

D. What

解析：考查非限制性定语从句，as引导非限制性定语从句，指代整个主句的内容，在从句中做主宾表，这句话as代替的是the Amber Room belongs to the Russians.在从句中做主语，句意:正如大家都知道的，琥珀屋是属于俄罗斯的。选A。