Final answer:
The United States acquired Puerto Rico as a result of the Spanish-American War.
Step-by-step explanation:
The territory acquired by the United States as a result of the Spanish-American War was Puerto Rico. After the war, Spain ceded Puerto Rico to the United States under the terms of the Treaty of Paris in 1898. Puerto Rico became an unincorporated territory of the United States, meaning its residents were U.S. citizens but did not have full representation in Congress.
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