20 points i beg you pl

what conclusion can be made about the location of egypt's major cities?
a. the flow of the nile river ran south, so more cities were located in the north. b. egyptians built cites in a north-south direction to take advantage of wind power. c. cities were located along the nile river to take advantage of the annual flooding. d. egyptian cities were located a far apart because there was a lot of warfare.