BOTH INTERNATIONAL & INLAND Which vessel may show three lights in a vertical line, the top and bottom being red and the middle being white?

Correct Answer: Option C — A vessel engaged in diving operations

Under Inland Navigation Rules, for the condition where 'Which vessel may show three lights in a vertical line, the top and bottom being red and the middle being white', the correct requirement is: 'A vessel engaged in diving operations'. This standard ensures clear navigational intent and collision avoidance.