What did the Monroe Doctrine do? A. It established an American protectorate over the Western Hemisphere.
B. It declared war on Spain because of Spain's colonization of South America.
C. It encourage European colonization of the Americas.
D. It formed an alliance between the United States and Britain.

A- It established an American protectorate over the Western Hemisphere.

Explanation:

The Monroe Doctrine is the best known U.S. policy toward the Western Hemisphere. Buried in a routine annual message delivered to Congress by President James Monroe in December 1823, the doctrine warns European nations that the United States would not tolerate further colonization or puppet monarchs.

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