Answer:
Texas
Step-by-step explanation:
A reason the United States was able to acquire Florida in the Adams-Onís Treaty was that it agreed to give up claims on Texas.
This is evident in the fact that the Adam-Onis treaty which was signed in 1819 between the USA and Spain was based on tenet in which Florida was ceded to the USA, while the United States agreed to give up claims of Texas in return.