无码高清视频|成人自拍视频|欧美成人午夜无码A片秀色直播|草美女视频网站|美女被操网站在线观看

單項選擇題

Changing rescuers while carrying out artificial respiration should be done().

A.without losing the rhythm of respiration
B.only with the help of two other people
C.by not stopping the respiration for more than 5 minutes
D.at ten-minute intervals

微信掃碼免費搜題