The correct answer is Egypt.The Nile is the longest river in the world.It flows across the eastern African region from South to North.The major portion of the river flows in Egypt.It is the source for agriculture, fishing and facilitates transportation in the country.Additional InformationIts basin covers countries like Uganda, Sudan, South Sudan,Ethiopia and Egypt. It starts near Lake Victoria(near Uganda) and empties into the Mediterranean Sea(Egypt).The main tributaries are White Nile (from Lake Victoria) and Blue Nile (from Ethiopia).It is a major lifeline for the countries in the eastern Sahara region.It provides transportation and supports agriculture and fishing in the region.Alexandria, Cairo(Egypt) and Khartoum(Sudan) are the important cities on the bank of the river.