Which river is noted for forming the world’s third-largest drainage basin?

The Mississippi River is recognized for forming the world’s third-largest drainage basin, which encompasses a vast area of the central United States and parts of Canada. This drainage basin extends over 1.2 million square miles, collecting water from numerous tributaries and contributing to a diverse ecosystem rich in wildlife and plant species. The Mississippi's basin plays a significant role in agriculture, shipping, and transportation, serving as a vital artery for commerce in the region.

In contrast, the Ohio River drainage basin, while significant, is smaller and primarily feeds into the Mississippi. The Columbia River, located in the Pacific Northwest, has a substantial basin as well but does not rival that of the Mississippi in size. The Mackenzie River, although large, is primarily significant in its own northern territory and does not compare to the expansive reach of the Mississippi River's drainage area.