On 3 December evening twilight for your vessel will occur at 1901 zone time. Your vessel's DR position will be LAT 24°18.5' S, LONG 110°30.6' W. Considering their magnitude and location, what are the three stars best suited to observe for a fix at star time?

Correct Answer: Option C — Alpheratz, Achernar, Nunki

For a fix at twilight, select stars with a wide azimuth spread (ideally 120° apart) and moderate altitudes (between 20° and 70°). Alpheratz, Achernar, and Nunki provide optimal geometry for the observer's latitude in the Southern Hemisphere, ensuring accurate lines of position.