单项选择题
A.25% B.50% C.100% D.12.5% E.2.5%
A.100% B.50% C.25% D.12.5% E.0
A.胎头受压 B.胎儿过度成熟 C.胎儿宫内窘迫 D.胎盘功能低下 E.脐带受压