单项选择题
（） is (are) not power supplied by main switchboard directly.
A.Steering gear and windlass B.Navigation light and radio power panel C.Navigation device power box D.Daily fresh water pump
单项选择题 （）is power supplied by main switchboard directly not through sub-board.
单项选择题 （）are located on the road panel of main switchboard.
单项选择题 Insulation light is located on.（） of main switchboard.
