PLEASE HELP!! Most of the major cities pictured in the map are located where they are because of which of the following?

A. The trading caravans used the Nile to travel to markets in Lake Nasser.

B. Water features make mining easier than farming.

C. The only source of water in the country is along the Nile River.

D. The flooding of the Nile River deposited silt that made good farmland.