单项选择题
If you are transmitting a distress message by radiotelephone you should（）.
A.use English language B.always use the International Code C.preface it by the word SOS D.follow the transmission with the radio alarm signal
单项选择题 A person who sees someone fall overboard should（）.
单项选择题 （）is the most visible signal of distress from a lifeboat at sea in the daytime.
单项选择题 Which signal is recognized as a distress signal?（）.
