A.the vessel is in distressB.the vessel has completed l……

单项选择题All of the following are distress signals EXCEPT（）.

A.the continuous sounding of any fog signal apparatus
B.giving five or more short and rapid blasts of the whistle
C.firing a gun at intervals of about a minute
D.a barrel with burning oil in it，on deck

单项选择题All of the following are distress signals under the Rules EXCEPT（）.

A.a green star signal
B.orange-colored smoke
C.red flares
D.the repeated raising and lowering of outstretched arms

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?（）.

A.MAYDAY sent by radiotelephone
B.Continuous sounding of fog horn
C.Green star shells fired from a launcher
D.Square flag and ball in a vertical line

单项选择题When two vessels are in immediate danger of collision，the stand-on vessel must（）.

A.abandon ship
B.assist in taking whatever action is necessary to avoid collision
C.hold course and speed
D.sound a distress signal