BOTH INTERNATIONAL & INLAND Which of the following describes a vessel exhibiting the lights shown in illustration D083RR below?

Correct Answer: Option B — not under command

Rule 27(a)(i) requires a vessel not under command (NUC) to exhibit two all-round red lights in a vertical line where they can best be seen. This distinct vertical red-over-red configuration immediately alerts other mariners that the vessel cannot maneuver as required.