BOTH INTERNATIONAL & INLAND In restricted visibility, a vessel which detects by radar alone the presence of another vessel shall determine if a close quarters situation is developing or risk of collision exists. If so, she shall __________.

Correct Answer: Option C — avoid altering course toward a vessel abaft the beam

Rule 19(d) of the Navigation Rules mandates that when avoiding a close-quarters situation detected by radar alone in restricted visibility, a vessel shall avoid altering course to port for a vessel abaft the beam, and avoid altering course toward a vessel abeam or abaft the beam.