Answer:
Ohio River. Missouri river
Explanation:
The historical evidence clearly indicates that the Ohio River did not exist before the last ice advances. Before Ohio and Missouri rivers, the major glacier drainage of the east-west direction happens in the Teays River. When the ice of the glaciers blocked the Teaya river valley, then Ohio was formed.
Like Ohio, the Missouri river did also not exist before the Pleistocene and during that time the largest drainage in North America takes place in the Hudson's Bay
