对接收的密级文件资料，要严格按（）妥善收存，并认真执行密级文件资料的借阅规定。
A、保密规定
B、密级分类整理后
C、借阅规定
D、单位规定
参考答案：A
栓塞最常见的风湿性心瓣膜病是（）。
A.二尖瓣关闭不全
B.主动脉瓣关闭不全
C.二尖瓣狭窄
D.主动脉瓣狭窄
E.三尖瓣狭窄
A 26-year-old primigravida is in labor. Her cervix is 5 cm dilated and 75% effaced; the fetus is at 0 station. The client requests medication to relieve the discomfort of contractions, and the physician prescribes an epidural regional block. What position should the nurse help the client to assume when the epidural is administered（）
A. Lithotomy.
B. Supine.
C. Prone.
D. Lateral.
