单项选择题
A person who observes an individual fall overboard from an OSV should（）.
A.immediately jump into the water to assist the individual B.call for help and keep the individual in sight C.run to the radio room to send an emergency message D.go to the control room for the distress flares
单项选择题 A man aboard a vessel，signaling by raising and lowering his outstretched arms to each side，is indicating（）.
单项选择题 If you see someone fall overboard from a vessel，you should（）.
单项选择题 A sound signal of seven short blasts and one long blast given with the vessel’s sound system is（）.
