BOTH INTERNATIONAL & INLAND At night, you see the display of lights shown in illustration D074RR below. These lights indicate which vessel?

Correct Answer: Option A — a sailing vessel

Rule 25(a) states that a sailing vessel underway shall exhibit sidelights and a sternlight. These lights indicate the vessel is under sail and not using its engine for propulsion, which is essential for determining right-of-way under the steering and sailing rules in Part B.