单项选择题
A.Fuel supply line valve
B.Pressure registered on the accumulator gauge
C.Cold-spark voltage readings test lamp
D.Engine stop control
单项选择题 Aluminum lifeboats are subject to damage by electrolytic corrosion (the aluminum being eaten away). In working around boats of aluminum you must be very careful（）.
单项选择题 All inflatable liferafts have（）.
单项选择题 After conducting an abandonment drill，the Master or person in charge of a ship shall log（）.