单项选择题
Which categories of NAVTEX messages may not be selectively rejected through receiver programming?（）
A.Navigational warnings B.Weather warnings C.SAR and distress alert information D.All of the above
单项选择题 Which action should you take after sending a false distress alert on VHF?（）
单项选择题 When you are firing a pyrotechnic distress signal，it should be aimed at（）.
单项选择题 When should distress flares and rockets be used? （）
