In the 19th century, which of these river was an important route for transporting goods from northern states to southern states?

"There were a number of important routes, but at the time rivers were the most important. The Mississippi, Missouri, Ohio, and Susquehanna rivers were all key modes of transport for northern goods heading to southern states. Several oceanic routes were also used, connecting northern ports like New York and Boston to southern ports like Charleston, Mobile, and New Orleans via the Atlantic Ocean and the Gulf of Mexico."

"The least convenient route was overland, as roads were still of very poor quality and it was far less efficient to haul goods using carts and livestock when compared to using boats on waterways."
-hope tht helps :)