Answer:
Option: B) It served as a warning to European nations to not try and re-colonize Latin America because the U.S. would intervene.
Explanation:
The Monroe Doctrine was a foreign policy issued in 1823 during the presidency of James Monroe. The Monroe Doctrine threatens European nations that the United States would not allow more colonization and monarchs rule in the Western Hemisphere. The doctrine also helped colonies in North and South America to adopt democratic government.