Your vessel has been damaged and is taking on water，but you do not require immediate assistance. You would preface a message advising other vessels of your situation with（）.

单项选择题The urgency signal concerning the illness of persons on board ship is（）.

A.MAYDAY
B.PAN
C.SECURITE
D.ATTENTION

单项选择题If you wished to transmit a message by voice concerning the safety of navigation，you would preface it by the word（）.

A.Mayday
B.Pan-pan
C.Securite
D.Safety