I would think that it is C but I'm not that sure so get more answers.
The western settlement continued to force native americans off their land.
The answer is, To argue for, there's the obvious, which is that the colonists didn't
like their lack of voice within British Parliament. They also didn't
like how Britain was treating other colonies, what would become Canada
for instance, with similar laws and codes seen in the US colonies. You
could also argue that it was a more financial decision, as the taxes
placed upon the colonies and the restrictions on trade were hurting
American businesses. Honestly, an argument combining the two would
probably be more rounded.