Which city is served by the airport code NAS?

The airport code NAS corresponds to Nassau, which is the capital city of the Bahamas. Each airport around the world is assigned a unique IATA airport code that typically reflects the name of the city or the airport itself. Nassau's airport is the primary international gateway to the Bahamas and is officially named Lynden Pindling International Airport, thus reinforcing the connection between the code and its geographical location.

In this case, the other choices represent different cities with their respective airports that do not match the NAS code. Newark, New Jersey has the airport code EWR, New York has multiple airports with codes such as JFK for John F. Kennedy International Airport, and New Orleans has its own airport code MSY for Louis Armstrong New Orleans International Airport. Therefore, the correct response indicating that NAS is associated with Nassau, Bahamas is based on the unique identification system used for airports worldwide.