A passenger vessel is underway. When may passengers visit the pilothouse?

Correct Answer: Option C — Passengers are excluded from the pilothouse while underway.

To maintain navigational safety and prevent distractions, 46 CFR 185.420 prohibits passengers from entering the pilothouse while the vessel is underway. This regulation ensures the Master and the officer of the watch remain focused solely on the safe operation, lookout duties, and navigation of the vessel without unauthorized interference.