It is not so much the possible trouble caused by helping others _______ people’s unwillingness to show their sympathy _________ accounts for the present situation.

A．as; as

B．as; that

C．that; which

D．that; as

现在有三个方案可供选择，其有关数据如表所示，其中最优方案为（）。

A．方案A 

B．方案B 

C．方案C 

D．方案B和C