INLAND ONLY You are on a power-driven vessel "I" as shown in illustration D036RR below. Vessel "II" is a power-driven vessel engaged in fishing that will pass within 1/2 a mile of your vessel. You sound one short blast on the whistle. Vessel "II" does not sound any signal. Which action should you take?

Correct Answer: Option A — Sound the danger signal and reduce speed.

Rule 34(d) requires that if a vessel fails to understand the intentions of another, or is in doubt whether sufficient action is being taken, it must immediately sound the danger signal (at least five short and rapid blasts). You must also reduce speed to assess the situation safely.