It is very strange that a beautiful young girl ____ have married that old a man. [ ]

A. should

B. would

C. might

D. could

某地区标准冻深为1.8m，地基由均匀的碎石土组成，场地位于城市市区，该城市市区人口为35万人。冻土层内冻前天然含水量的平均值为16%，冻结期间地下水位距冻结面的最小距离为1.5m，则该地区基础的设计冻深为（）m。

A．1.8

B．2.04

C．2.27

D．2.15