The correct answer is A)Desire for freedom
Since independence means Freedom
A) A fort was established and many were killed by diseases
Lewis and Clark's expedition was not positive to the native of Mandan village the most devastating epidemic was the smallpox outbreak in the year 1837 killing a lot of people. The epidemic played an important factor in uniting the surviving Mandans and Hidatsa who later engaged in trade, farming and hunting.
Modern day Iran hope it helps
fight for the lords, land and military protection