Under the President of Thomas Jefferson, Lewis and Clark began a journey from North frontier towards the western region of the US to explore the geographic features of the landscape and the people who inhabited those regions.
The expedition was significant as they discovered more than hundred specimen of biological plant life and animal kinds. They were welcomed and befriended by many native nevertheless a few had shown their unfriendliness towards them.
Their mission was to re-establish trade and business routes to India to declare American dominion.
Answer: i think its B
B. Americans extended the frontier when they learned about the territory from the expedition reports.
