To children, good habits do not come        , so parents and teachers need to be their role models.

A．instantly

B．automatically

C．eventually

D．steadily

23岁初产妇，妊娠39周，规律宫缩3小时，枕右前位，胎心136次／分，骨盆外测量未见异常，B型超声测胎头双顶径9．6cm，羊水平段3．0cm。

此时最恰当的处置应是（）.

A.行剖宫产术

B.静脉滴注缩宫素

C.缓慢静注能量合剂

D.肌注维生素Kl

E.严密观察产程进展