Final answer:
The correct option is A) Ceded Florida to the United States.
Step-by-step explanation:
The correct option that completes the statement about Andrew Jackson's success in the first Seminole War and its impact on the Adams-Onís Treaty is A) Ceded Florida to the United States.
Under Jackson's command, U.S. troops aided by Cherokees and Creeks defeated the Creek and Seminole militants and occupied several Florida settlements. Outraged by the U.S. invasion, the Spanish government ceded Florida to the United States in the Adams-Onís Treaty, which made the cession official. In exchange, the United States forgave Spain's $5 million debt.