Which vessels show only sidelights and a sternlight?

Non-power driven vessels, such as sailing vessels, are required to show only sidelights and a sternlight when under sail. The sidelights indicate the port and starboard sides of the vessel, helping other vessels identify its orientation and direction, while the sternlight is positioned at the stern to show the vessel's position from the rear. This lighting configuration is designed to enhance visibility and safety on the water by providing the necessary information to other vessels regarding the presence and movement of the non-power driven vessel.

Power-driven vessels, on the other hand, typically display additional lights to indicate their type and operational status, including a masthead light and possibly additional lights if they are engaged in activities like towing or fishing. Similarly, military vessels may have unique lighting configurations that reflect their operational status or adherence to specific regulations not applicable to non-power driven vessels. Therefore, the choice indicating that only sidelights and a sternlight are displayed is specifically accurate for non-power driven vessels.