Iguazu Falls spans the border between which two countries?

Iguazu Falls is a massive waterfall system located on the border between Argentina and Brazil. It is one of the most stunning natural wonders in the world, comprising approximately 275 individual falls along the Iguazu River. Most of the falls are located within the Iguazu National Park in Argentina, while part of the falls and the viewing area are situated in Brazil's Iguaçu National Park.

The unique geography and the international significance of Iguazu Falls make it a prominent tourist attraction shared by these two countries. The falls are generally recognized as a symbol of the natural beauty that can exist in cross-border regions, highlighting the rich ecosystems and biodiversity in both Argentina and Brazil.

In contrast, the other pairs of countries do not share this specific natural feature, making the Argentina and Brazil pairing the only correct answer in this context.