Which airport code corresponds to a major city in France?

The airport code B, CDG, corresponds to Charles de Gaulle Airport, which is located in Roissy-en-France, near Paris, France. This airport is named after Charles de Gaulle, the prominent leader of France during World War II and later its president. CDG is one of the busiest airports in Europe and serves as a major international gateway for flights traveling to and from France. Its significance in international air travel makes it unmistakably tied to Paris, one of the world's most prominent cities.

In contrast, the other airport codes do not relate to major cities in France. PIA is the code for General Wayne A. Downing Peoria International Airport in Illinois, PNS relates to Pensacola International Airport in Florida, and ONT stands for Ontario International Airport in California. Each of these airports serves different regions in the United States and is not associated with France or its major cities.