Final answer:
Belize has the largest barrier reef in the Western Hemisphere, known as the Belize Barrier Reef, which contributes to the country's ecotourism.
Step-by-step explanation:
The country that has the largest barrier reef in the Western Hemisphere is Belize. This nation is located on the eastern coast of Central America and boasts the longest coral reef in the region. The Belize Barrier Reef is a major tourist attraction, known for its rich biodiversity and stunning marine landscapes. It is a critical component of the Mesoamerican Biological Corridor and contributes significantly to Belize's ecotourism industry.
While Australia is home to the Great Barrier Reef, the largest barrier reef in the world, it is not located in the Western Hemisphere. Therefore, the answer to the question is not Australia, which is commonly mistaken due to the fame of its reef. Mexico, Brazil, and the United States also have coral reefs, but none of them are as extensive as the Belize Barrier Reef within the Western Hemisphere.