Regulations require that prior to departure on a three-day voyage, the steering gear, whistle, and communications system between the bridge and engine room must be tested prior to departure no earlier than __________.

Correct Answer: Option D — 12 hours

46 CFR mandates that steering gear, whistles, and bridge-to-engine room communication systems must be operationally tested within 12 hours prior to departing on any voyage exceeding 24 hours.