Which river is conventionally regarded as the longest river in the world?

The correct answer is B, Nile. The Nile flows north through north-eastern Africa for about 6,650 kilometres to the Mediterranean and is the river taken as the longest in the world in almost every textbook and examination. Its two great branches, the White Nile and the Blue Nile, meet at Khartoum in Sudan.

Option A, the Amazon, is the largest river in the world by the volume of water it discharges and by the area of its basin, which holds the largest rainforest; some surveys that measure it from a different headstream in the Andes also claim it as the longest, but that reading is not the one papers expect. Option C, the Yangtze, is the longest river of Asia and flows entirely within China. Option D, the Mississippi with the Missouri, is the longest river system of North America. Read the wording carefully, since longest and largest give different answers here.