单项选择题
A.502/120/2 B.502/120/3 C.110/120/2 D.110/120/3
A.502/2 250/3 B.502/2 250/2 C.110/2 250/3 D.110/2 250/2
A.502/250/3 B.502/50/2 C.110/250/3 D.110/250/2