INLAND ONLY Which light display would mark the opening in a pipeline where vessels could pass through?

Correct Answer: Option C — Two red lights in a vertical line on each side of the opening

Under Inland Navigation Rules, for the condition where 'Which light display would mark the opening in a pipeline where vessels could pass through', the correct requirement is: 'Two red lights in a vertical line on each side of the opening'. This standard ensures clear navigational intent and collision avoidance.