What is the proper action if your vessel is being overtaken by another vessel?

Answer: C — Keep your course and speed

When a vessel is being overtaken by another vessel, the correct action is to maintain your course and speed. This is in accordance with the navigation rules that dictate the responsibilities of vessels when overtaking occurs. The overtaking vessel is responsible for ensuring that it passes safely without altering the course or speed of the vessel being overtaken. By keeping your course and speed, you provide the overtaking vessel with a clear and predictable path, allowing them to maneuver safely past you. It is crucial for the overtaking vessel to assess the situation and adjust their navigation as needed, rather than requiring the vessel being overtaken to adjust its path. Altering course to starboard or port would be unnecessary and could create confusion regarding your intentions, potentially leading to dangerous situations. Similarly, sounding the horn while maintaining speed doesn't contribute to safety unless there's a specific danger that requires signaling to the overtaking vessel. Hence, maintaining your course and speed is the most prudent action in this scenario.