D Native Americans interacted and cooperated with the explorers.
Explanation:
Their mission was to explore the unknown territory, establish trade with the Natives and affirm the sovereignty of the United States in the region. One of their goals was to find a waterway from the US to the Pacific Ocean.
Famously, Sacagawea helped them on their journey at only 16! and she was pregnant at the time. She and her people knew the land well and helped them reach the pacific and navigate the Louisiana purchase to the Pacific Ocean.
