________the help of the teacher, the student who wasn't good at math________the difficult

problem quickly. [ ]

A. Under; worked out  

B. With; worked on

C. Under solved  

D. With; solved

初孕妇，26岁，妊娠40周，宫缩持续40秒，间歇5～6分钟，强度中等，胎心率154次/分，胎头先露已1小时无进展， * * 检查无异常，应诊断为( )

A．协调性宫缩乏力
B．不协调性宫缩乏力
C．骨产道异常
D．胎位异常
E．胎儿窘迫