单项选择题
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
A power-driven vessel leaving a quay or wharf must soun...
单项选择题A power-driven vessel leaving a quay or wharf must sound what signal? （）
A.Three short blasts B.A long blast C.A prolonged blast D.No signal is required
A light used to signal passing intentions must be an（）....
单项选择题A light used to signal passing intentions must be an（）.
A.alternating red and yellow light B.alternating white and yellow light C.all-round white or yellow light D.all-round white light only
A fishing vessel is approaching a vessel not under comm...
单项选择题A fishing vessel is approaching a vessel not under command. Which statement is TRUE? （）
A.The fishing vessel must keep clear of the vessel not under command B.If the vessel not under command is a power-driven vessel，she must keep clear of the fishing vessel C.They must exchange whistle signals D.Both vessels are required to take action to stay clear of each other
