单项选择题
A.To avoid immediate danger
B.When authorized by the rig superintendent
C.To comply with an operator's requirement
D.Under no conditions
单项选择题 Two vessels meeting in a “head-on” situation are directed by the Rules to（）.
单项选择题 Two vessels are in an overtaking situation.Which of the lights on the overtaken vessel will the overtaking vessel see（）.
单项选择题 Two barges are being pushed ahead by a tugboat.Which statement is TRUE concerning lights on the barges（）.