You are approaching another vessel and see that it has the signal flag "O" hoisted. What is your next action?

Correct Answer: Option A — Attempt to call the vessel on VHF radiotelephone and begin a search because the vessel has a man overboard.

International Code Flag "O" stands for "Man Overboard." Upon sighting this flag, a vessel must immediately attempt VHF radio contact and initiate search and rescue operations to locate the missing person.