引起腰腿痛最常见的病因是（）。
A.肿瘤
B.结构性缺陷
C.退行性变
D.风湿性脊柱炎
E.结核
参考答案：C
It has been suggested that the land equally among the farmers.
A．is shared
B．should share
C．be shared
D．will be shared
屋顶平面图附近常配以哪些节点详图
