单项选择题
A.水流和波浪荷载 B.堆货荷载 C.地震荷栽 D.冰荷载和风荷载
A.6/6 B.1/6 C.1/10 D.1/30
A.5%~20% B.20%~50% C.50%~80% D.>80%