单项选择题
The term of Landfall means（）.
A.Land first sighted when vessel approaching from seaward B.Land last sighted when vessel leaving from a port C.In sight of one another when vessel underway D.In sight of an island during a ship on her voyage
单项选择题 Preferred channel marks are colored with（）．
单项选择题 Preferred channel marks are aids to navigation which all following marks other than（）．
单项选择题 In the absence of a route leading from seaward，the conventional direction of buoyage generally follows（）.
