Final answer:
The lights that a vessel must exhibit include the masthead light, sidelights, and sternlight, to ensure it is visible and its orientation, heading, and status are clear to other vessels.
Step-by-step explanation:
The question you've asked pertains to the lights that a vessel is obligated to exhibit in order to comply with maritime navigation rules. The correct lights a vessel must display are:
a) Masthead, sidelights, and sternlight
This set of lights helps other vessels identify the type and orientation of the ship, its heading, and status. The masthead light is a white light located on the fore and aft centerline of the vessel. Sidelights are red (to port) and green (to starboard) lights that show an unbroken light over an arc of the horizon of 112.5 degrees. The sternlight is a white light placed as nearly as practicable at the stern showing an unbroken light over an arc of the horizon of 135 degrees and so fixed as to show the light 67.5 degrees from right aft on each side of the vessel.