What should you do if you see a red flag being raised on another vessel?

When you see a red flag being raised on another vessel, it serves as a warning sign indicating that there is a specific danger or emergency situation on board. It is a universal maritime signal that signifies to other vessels that they should keep their distance. Therefore, the appropriate action is to maintain a safe distance from the flagged vessel to avoid any potential hazards associated with the situation on board.

Keeping clear of the vessel allows you to ensure your own safety and the safety of those on the flagged vessel. It is essential to respect these signals in marine environments to avoid accidents, particularly if there is a risk of divers in the water or other dangerous conditions. Maintaining distance ensures that you do not inadvertently interfere with any ongoing emergency response or create an unsafe situation for yourself or others.

The other choices would not prioritize safety in this situation. Approaching the vessel could increase the danger to yourself and perhaps those on board the other vessel. Ignoring the red flag can lead to serious consequences, as it shows a lack of awareness towards critical signals. Signaling back would not be effective or appropriate in such a situation where immediate action should be focused on safety, rather than communication.