What does the signal "_ _ . OR ." indicate in terms of overtaking?

Answer: B — The vessel intends to overtake on the starboard side

The signal "_ _ . OR ." specifically indicates that the vessel intends to overtake on the starboard side. This is derived from the International Regulations for Preventing Collisions at Sea (COLREGs), which state that when a vessel sounds one prolonged blast followed by one short blast, it is a signal for the intention to pass another vessel on its starboard side. Understanding the context is important: the signaling system is designed to ensure safe navigation and communication between vessels, indicating intentions clearly to avoid confusion and potential collisions. Each specific combination of sounds conveys a precise message to other vessels regarding actions to be taken. Thus, recognizing this sequence of signals is crucial for maintaining navigational safety and adhering to maritime regulations.