What method did the union use to stop most of the south’s cotton trade

The Union used a large naval blockade to stop most of the South's cotton trade. I hope this helps!

(d) rivers.

explanation:

civilizations developed around rivers because their waters provided places to hunt and fish. also, as the rivers flooded, the lands around them became fertile. this allowed them to support farming. this is especially true of the nile river, which flooded the same time each year.