What lights indicate an anchored vessel at night?

The correct indication of an anchored vessel at night is represented by two red lights shown in a vertical line. This configuration is established under the International Regulations for Preventing Collisions at Sea, also known as COLREGs, which dictate how vessels should signal their status to avoid misunderstandings and ensure safety on the waterways.

When a vessel is at anchor, it must display two red lights; this clearly communicates to other vessels that it is not underway and is stationary. The vertical arrangement of these lights allows for easy identification from a distance and at various angles, making them effective for visual recognition by other mariners.

Other options, while they may represent different scenarios or vessels, do not accurately convey the status of an anchored vessel. This understanding is crucial for navigational safety and awareness on the water.