单项选择题
What is NOT a distress signal?（）.
A.Red flares or red rockets B.Continuous sounding of fog signaling apparatus C.International Code Flags November and Charlie D.Basket hanging in the rigging
单项选择题 What would NOT be a distress signal?（）.
单项选择题 When two vessels are in immediate danger of collision，the stand-on vessel must（）.
