单项选择题
In a narrow channel, a signal of intent which must be answered by the other vessel, is sounded by a vessel（）.
A.meeting another head-on B.crossing the course of another C.overtaking another D.Any of the above
单项选择题 In a traffic separation scheme, when joining a traffic lane from the side, a vessel shall do so（）.
单项选择题 In a weather report, position good means that the position is（）.
