Question 439 Rules of the Road

You are correct, the answer is A) A vessel constrained by her draft. The reason this is the correct answer is that according to the International Regulations for Preventing Collisions at Sea (COLREGS), a vessel constrained by her draft is required to display three all-round red lights in a vertical line at night to indicate her status. The other answer choices are incorrect because they do not correspond to the lighting requirement for a vessel constrained by draft. A vessel aground, a vessel dredging, or a vessel moored over a wreck would have different lighting configurations.