As is well known，Dragon Boat Festival and the custom of eating rice dumplings are ________ to us

Chinese.[ ]

A．typical  

B．unique

C．alone  

D．special

具有足够的强度、整体性、均一性、（）、耐久性是各类水工建筑物对地基基础的基本要求。

A．稳定性 

B．抗渗性 

C．抗冻性 

D．可塑性