单项选择题
A.At least one fire and drill shall be held within 24 hours of leaving a port where more than 25 percent of the crew has been replaced
B.The Master is responsible in seeing thst each lifeboat is lowered to the water at least once in each 6 months
C.Lifeboat equipment shall be examined at least once each month to insure that it is complete
D.An entry shall be made in the vessels official Logbook relative eo each fire and boat drill
单项选择题 （）refers to the angle between true North and heading line of the vessel.
单项选择题 （）the incomplete nature of the survey ,heavy draught vessels warned not to navigate within the 10 fathom line.
单项选择题 （）the survivors known more of how to cope with cold water in the sinking of MV Titanic in 1912 countless lives（）.