Question 516 Rules of the Road

The correct answer is D) Two red. According to the International Regulations for Preventing Collisions at Sea (COLREGS) and the Inland Navigation Rules, a power-driven vessel "not under command" at night must show two red lights in a vertical line to indicate its status. This signifies that the vessel is unable to maneuver as required and other vessels must keep clear. The other options are incorrect because they do not match the regulatory requirement for a "not under command" vessel. Three white lights or two white lights would indicate a different status, while three red lights is not the prescribed lighting arrangement for this situation.