The correct option is A Niger
The region of Niger river is one of the most populous countries of Africa. The Niger River is the principal river of West Africa, extending about 4,180 km. The Niger is the third-longest river in Africa, exceeded only by the Nile and the Congo River. The majority of the people in the region of Niger river were those from the colonial Calabar, Itsekiri and Ogoja divisions, the present-day Ogoja, Itsekiri, Annang, Ibibio, Oron, Efik, Ijaw and Ogoni peoples.