单项选择题

A.睡眠过程中口鼻气流停止≥5s
B.睡眠过程中口鼻气流停止≥10s
C.睡眠过程中口鼻气流停止≥20s
D.睡眠过程中口鼻气流停止≥30s
E.睡眠过程中口鼻气流停止≥1min