单项选择题
A.set it on the centerline of the boat B.apply the correction for compass error C.keep metal objects away from it D.All of the above
A.remove their life preservers to make it easier to climb on board the rescue vessel B.climb on top of the boat while waiting for their turn to transfer to the rescue vessel C.remain seated inside and make the transfer one person at a time D.enter the water and swim over to the rescue vessel
A.fuel supply valve should be closed B.hatches，doors，and oar ports should be closed C.air cylinder shut-off valve should be closed D.engine should be shut off