Map title is "Westward Expansion." Map is a physical map of the United States. The Appalachian Mountains are labled on the east coast running from the center north. The Mississippi River runs from the Gulf of Mexico in the south north to the Great Lakes region. The Missouri River branches from the Mississippi to the west and the Ohio River branches from the Mississippi to the east. In the western part of the map, the Rocky Mountains span the north-south region. There is a compass rose on the map indicated north to the top of the map. On the overall map, the map areas in the west are brown except the areas bordering the Pacific Ocean, and the map areas around the Appalachian Mountains are brown. The remainder of the map is green. Review the map of the United States. Which answer best explains how the Lewis and Clark expedition managed food resources as they moved westward?

They learned to use the plants and animals most available in each region.
They learned that carrying trinkets for trading with native tribes for food would be easier than hunting for their own food.
They realized they would be out of options for food by the time they reached the Rocky Mountains.
They realized they should have carried more familiar foods with them so that they could avoid eating strange new things.