单项选择题
A power-driven vessel pushing aheador towing alongside displays navigation lights and（）.
A.two all-round red lights in a vertical line B.two yellow towing lights in a vertical line C.two white masthead lights in a vertical line D.two lights on the stern，one yellow and one white
单项选择题 A power-driven vessel leaving a quay or wharf must sound what signal? （）
单项选择题 A light used to signal passing intentions must be an（）.
单项选择题 A fishing vessel is approaching a vessel not under command. Which statement is TRUE? （）
