Question 950 Rules of the Road

The correct answer is A) A vessel at anchor. The International and Inland Navigation Rules state that a vessel at anchor must sound a fog signal consisting of one short blast, one prolonged blast, and one short blast in quick succession. This distinctive signal helps alert other vessels in the vicinity of the presence and location of the anchored vessel, especially in poor visibility conditions like fog. The other answer choices are incorrect because they do not accurately describe the fog signal requirement for those vessel situations. A vessel not under command, a vessel towing, or all vessels in general do not use this particular fog signal pattern.