What was the original purpose of the Lewis and Clark expedition?

The original purpose of the Lewis and Clark expedition was to explore the newly acquired Louisiana Territory and to find a water route to the Pacific Ocean. Following the Louisiana Purchase in 1803, President Thomas Jefferson commissioned Meriwether Lewis and William Clark to undertake this journey. Their main objectives included mapping the uncharted territories, establishing trade relationships with Native American tribes, and identifying the most feasible routes for commerce and transportation.

This expedition significantly contributed to the understanding of the geography, biology, and ethnography of the western territories, while also bolstering the United States' claims to lands acquired through the Louisiana Purchase. The expedition yielded important information about the natural resources, potential trade routes, and the cultures of the indigenous peoples encountered along the way, all of which were vital for the nation’s expansionist agenda during that era.

In contrast, the other options do not accurately reflect the mission's purpose or context. The ideas of conquest of Native lands and documenting agricultural practices were not central objectives of the expedition, and exploring already settled eastern territories does not pertain to the expedition's goals, as it mainly focused on uncharted western territories.