The area near the indus and ganges rivers is one of the most densely populated areas of the south asian subcontinent because of its a. lush rain forests. c. ocean ports. b. fertile land. d. high mountains.

I think its B. Fertile Land because the Gangas and Indus river are very helpful with making the land more fertile. When land is more fertile it is easier to farm, so people go there to start farming and then they can feed themselves and their family.

Again the answer is B. Fertile land