Approaching a green sidelight means?

• A. Stop
• B. Go
• C. Maintain course
• D. Slow down

Answer: (B)

The main idea is using navigation lights to judge relative positions and right-of-way at night. A green sidelight marks the starboard (right) side of a vessel. When you’re approaching a green sidelight, you’re effectively dealing with a vessel on its starboard side, which means you’re the stand-on vessel in a crossing situation and may continue on your current course and speed. In other words, you don’t need to alter course just because you see that light; proceed as planned unless you detect an imminent risk of collision. If instead you saw a red sidelight, that would indicate the other vessel is on your port side and you’d typically need to take action to avoid.