BOTH INTERNATIONAL & INLAND You see a red sidelight bearing NW (315°). That vessel may be heading __________.

Correct Answer: Option A — southwest (225°)

A red sidelight spans an arc of 112.5 degrees from dead ahead to 22.5 degrees abaft the port beam. Observing a red light bearing NW (315 degrees) indicates the vessel is showing its port side, meaning it must be heading toward the southwest (225 degrees).