The correct answer is A. Spain realized that the expense and trouble of maintaining Florida outweighed its usefulness and agreed to sell it.
The First Seminole War (1817-1818), catalyzed by conflicts between American settlers and Seminole tribes, exposed Spain's inability to effectively govern Florida and maintain order in the territory. This situation, combined with increasing pressure from the United States, eventually led Spain to consider selling Florida to the U.S., which culminated in the Adams-OnĂs Treaty of 1819.