Which airport code is associated with San Francisco?

The airport code associated with San Francisco is SFO. This code stands for San Francisco International Airport, which is the primary airport serving the San Francisco Bay Area. It is well-known and widely recognized, making it an essential identifier for flights into and out of the region. The use of three-letter codes for airports is a standard established by the International Civil Aviation Organization (ICAO) and is used by airlines and travelers for clarity in travel itineraries and logistics.

The other options do not relate to San Francisco. For example, SJD is the airport code for Los Cabos, Mexico; PVR is the code for Puerto Vallarta, Mexico; and PNS is for Pensacola, Florida. Each of these codes is linked to their respective airports in different regions, demonstrating that the correct code, SFO, specifically identifies San Francisco International Airport.