The correct answer is (Choice D) limit the westward expansion of British colonial settlement.
The map indicates a line separating indigenous territory from the colonies, which reflects the British government's efforts to restrain colonial settlers from encroaching on indigenous lands, particularly after the conflicts that arose during the French and Indian War. This line was part of the Proclamation of 1763, aimed at stabilizing relations with Native American tribes and preventing further conflict by limiting where colonists could settle.