Before us lies the biggest room with things like guns dolls and old clothes.A. fillingB.

问题补充：

Before us lies the biggest room, with things like guns, dolls and old clothes.

A. filling

B. filled

C. being filled

D. having been filled

答案：

A. filling

(答案→)B. filled

C. being filled

D. having been filled

解析：考查过去分词做定语，前面的句子是倒装句，提前地点状语，主语是the biggest room，过去分词filled with things修饰room，因为是be filled with、…，句意是：我们前面的是最大的房间，里面装满了枪，玩具和旧衣服。选B。