A client with hypotonic labor dysfunction is receiving oxytoein augmentation. Her contractions become more frequent and intense. Dilation progresses to 8 cm, but the fetal head remains at station +1. The nurse notes a soft bulge just above the symphysis. Which of the following actions is best

A. Re-evaluate the fetal presentation.
B. Change the client’s position.
C. Offer a narcotic analgesic.
D. Help the client urinat

对农村7岁易感儿童进行甲肝疫苗免疫，经3年随访观察，结果如下该疫苗的效果指数是（）

A.0.9

B.1

C.10

D.5

E.8