单项选择题
A.oil stained shoes or clothing
B.sharp objects that may puncture or damage the liferaft
C.matches or cigarette lighters
D.drugs or paraphernalia not approved by a medical doctor
单项选择题 On inflatable liferafts，the operating cord should be renewed by（）.
单项选择题 Inflatable liferafts shall be serviced at an approved servicing facility every 12 months or not later than the next vessel inspection for certification. However，the total elapsed time between servicing cannot exceed（）.
单项选择题 Inflatable liferafts are provided with（）.