What is the priority level and proper use of the urgency signal 'PAN-PAN' on VHF Channel 16?

1. The urgency signal (urgencia): used for an urgent message concerning the safety of a vessel or person, where there is no immediate, grave danger to life (e.g., disabled steering drifting in open water, serious medical injury)
2. The highest priority distress signal used when a ship is sinking immediately
3. A routine call used to request a weather forecast from a nearby yacht
4. A radio test phrase used to calibrate antenna power