The longest river in the world is the river.
a. indus
b. nile
c. mississippi
d. missouri

The longest river in the world is the Nile river.

Option B

Explanation:

Africa encompasses the river Nile with its water resources shared across 11 countries. A variety of old age Egyptians has raised its civilization where the Nile formed their main source of irrigation and freshwater.

Although Egypt and Sudan have many secondary sources of water, Nile serves as a primary source for them for agricultural and daily purposes. White Nile forms the primary stream of the Nile river with North East civilizations that were developed with the close existence of the Nile river.