单项选择题
In the absence of a route leading from seaward，the conventional direction of buoyage generally follows（）.
A.an anti-clockwise direction around land masses B.a clockwise direction around land masses C.an anticlockwise direction around sea masses D.a clockwise direction around sea masses
单项选择题 In regions where ice conditions prevail in the winter，（）.
单项选择题 A vessel shall not（）.
单项选择题 A sailing vessel shall not impede the safe passage of a（）．
