Which policy warned European powers against colonizing in the Western Hemisphere?

• A. Monroe Doctrine
• B. Roosevelt Corollary
• C. Open Door Policy
• D. Dollar Diplomacy

Answer: (A)

The Monroe Doctrine is being tested here. It was a statement issued in 1823 by President James Monroe that the Western Hemisphere was off-limits to new European colonization and that the United States would oppose any European interference in the Americas. It established a clear stance that European powers should not colonize or control new territories in the hemisphere, setting the stage for U.S. hemispheric influence. The Roosevelt Corollary later expanded on this idea by justifying intervention in Latin America, Open Door Policy dealt with equal rights in China, and Dollar Diplomacy used economic means to influence other nations. So the policy that warned European powers against colonizing in the Western Hemisphere is the Monroe Doctrine.