Final answer:
The Royal Proclamation of 1763 established the Proclamation Line to avoid conflict with Native American tribes and to manage the costs of defending new territories, aiming to uphold Indigenous land rights. Therefore, the correct option regarding the boundaries for the 13 colonies is 'c. Indigenous land rights'.
Step-by-step explanation:
The Royal Proclamation of 1763 was an important edict issued by the British monarchy following the conclusion of the Seven Years' War. Its primary purpose was to establish boundaries for the 13 colonies by declaring the Appalachian Mountains as the western limit of colonial expansion. This line was known as the Proclamation Line, and the key goal was to avoid conflict with Native American tribes and manage the costs associated with defending and administering new territories, which is in line with option c from the provided choices, Indigenous land rights.
The British government intended the Proclamation Line to be a temporary measure, giving them time to develop a more permanent policy. Moreover, this proclamation was seen by the colonists as an imposition, especially by those who had received land grants west of the Appalachian Mountains and viewed the restriction as a form of tyranny.
Consequently, the correct option in regards to the purpose of the Royal Proclamation in establishing boundaries for the 13 colonies is c. Indigenous land rights. The goal was not economic expansion, cultural preservation, or military defense directly, but rather to maintain peace and order by respecting the territories of Indigenous peoples and preventing further conflict on the frontier.