BOTH INTERNATIONAL & INLAND Your vessel enters fog. You stop your engines, and the vessel is dead in the water. Which fog signal should you sound?

Correct Answer: Option D — Two prolonged blasts every two minutes

Rule 35(b) mandates that a power-driven vessel underway but stopped and making no way through the water shall sound two prolonged blasts at intervals of not more than two minutes. This signal is distinct from the single prolonged blast used by a power-driven vessel that is making way.