Any alteration of course and／or speed to avoid collision shall，if the circumstances of the case admit，（）to another vessel observing visually or by radar.

单项选择题All of the following constitute special circumstances EXCEPT（）.

A.Three vessels meeting so as to cross each other's course
B.A vessel meeting a vessel that is backing out of a slip
C.An overtaking situation that has reached in extremis
D.A vessel fishing with nets meeting a sailing vessel

单项选择题All of the following are practices of good seamanship EXCEPT（）.

A.When meeting，altering course to the left to increase sea room
B.Maintaining an alert radar watch in reduced visibility
C.Showing a flare-up light to attract attention when you are not under command
D.Maintaining a proper lookout from sunrise to sunset

单项选择题A vessel restricted in her ability to maneuver is one which（）.

A.through some exceptional circumstance is unable to maneuver as required by the Rules
B.from the nature of her work is unable to maneuver as required by the Rules
C.due to adverse weather conditions is unable to maneuver as required by the Rules
D.has lost steering and is unable to maneuver

单项选择题A vessel is in sight of another vessel when she（）.

A.can be observed by radar
B.has determined that risk of collision exists
C.is sounding a fog signal which can be heard on the other vessel
D.can be observed visually from the other vessel

单项选择题A vessel is in sight of another vessel when（）.

A.she can be observed by radar
B.she can be observed visually from the other vessel
C.she can be plotted on radar well enough to determine her heading
D.her fog signal can be heard