The airport code BIS stands for which city?

The airport code BIS represents Bismarck, North Dakota, which is confirmed by the significant reference to the city in the ICAO airport code system. Each airport is designated a specific three-letter code that is distinct and reflects the airport's name or location, with BIS being the designated code for the capital city of North Dakota. This code is widely used in air travel operations, ticketing, and flight scheduling, making it critical for identifying Bismarck in transportation and logistics contexts.

The other options refer to different cities, each having their unique codes: Boise is represented by BOI, Boston's airport uses BOS, and Buffalo's airport has BUF. Thus, the distinctiveness of BIS clearly aligns with Bismarck.