This is the small house less than 15 square meters under roof lives a large family of th

问题补充：

This is the small house less than 15 square meters, under roof lives a large family of three generations.

A. which

B. that

C. its

D. whose

答案：

A. which

B. that

C. its

(答案→)D. whose

解析：考查定语从句。先行词是house，在定语从句under roof lives a large family of three generations中作roof的定语，所以选D。