单项选择题
The radiotelegraphy safety messages for condition indicating distress，urgency and safety，respectively，are（）.
A.SOS，ZZZ，XXX B.SOS，UUU，SSS C.SOS，XXX，TTT D.SOS，TTT，UUU
单项选择题 The most likely time for oil pollution while bunkering is when（）.
单项选择题 Smoking in bed on a ship is prohibited（）.
单项选择题 Should the vessel have no deratisation certificate at the time of her delivery，she（）be held to be unseaworthy.
