Select the reason cities tended to develop at the fall line on rivers.
a)the fall line is where rivers converge, which was beneficial for trade.
b)the fall line is the widest point along the middle of a river, so travel was easier.
c)the fall line is where rivers are no longer navigable by ships traveling in from the ocean, so goods had to be offloaded.
d) the fall line follows the ridge of the appalachian mountains, providing access inland where goods could be traded.