Answer:
South of a line connecting the course of the Sénégal River, the Niger River, and the southern two-thirds of Nigeria, Niger-Congo languages are spoken. Along the middle course of the Niger River and around Lake Chad, Nilo-Saharan languages related to those of peoples farther east predominate. These peoples are divided into a very complex ethnic mosaic but may often be conveniently classified by their individual languages.
Step-by-step explanation: