单项选择题
A vessel sounds one short blast. This signal indicates the vessel（）.
A.intends to alter course to starboard B.intends to pass starboard to starboard C.is altering course to starboard D.intends to pass port to port
单项选择题 A vessel not under command sounds the same fog signal as a vessel（）.
单项选择题 A vessel displaying three red lights in a vertical line is（）.
单项选择题 A vessel constrained by her draft may display（）.
