问题补充:
There are two small rooms in the house, serves as a kitchen
A. the smaller of which
B. the smallest of which
C. the smaller of them
D. the smaller one
答案:
(答案→)A. the smaller of which
B. the smallest of which
C. the smaller of them
D. the smaller one
解析:从结构看是非限定性定语从句,排除C、D(如果句子中间的逗号改成句号,则C、D正确),又因为是两者之间用比较级,排除B。