The correct answer is option B. "by raiding American settlements".
Explanation:
During American Revolution most of the Southeast Indians supported the British Empire against the United States or Spain. The way that Southeast Indians helped the British Empire was by raiding American settlements. The American settlements in the Carolinas and Georgia were among the most affected by the Southeast Indians, particularly by the Cherokees.
Also known as the Ordinance of 1787, the Northwest Ordinance established a government for the Northwest Territory, outlined the process for admitting a new state to the Union, and guaranteed that newly created states would be equal to the original thirteen states.