Question 1001 Rules of the Road

The correct answer is C) One short, one prolonged, and one short blast of the whistle. This signal is prescribed by the International Regulations for Preventing Collisions at Sea (COLREGS) and the Inland Navigation Rules for vessels at anchor in restricted visibility. The one short, one prolonged, and one short blast pattern is the required audible signal to warn an approaching vessel of the anchored vessel's presence. The other answer choices are incorrect because: A) Sounding the whistle continuously is not the prescribed signal, B) Five or more short and rapid blasts is the signal for an emergency, and D) Three distinct strokes on the bell is the signal for a vessel at anchor, but it must be accompanied by the one short, one prolonged, one short whistle blast.