What is the best explanation as to the dividing line between french and british claims in north america at this time?
a) france had won its territory from spain
b) britain had won its territory from spain.
eliminate
c) the appalachian mountains served as most of the boundary.
d) the mississippi river served as the boundary between the territories.

C) The Appalachian Mountains served as most of the boundary.

Explanation:

AS you can see in the map, the European Countries divided the territories in North America, between the three of them, and mostly by order of arrival or settlements, the border between the French and English territories in this map is given by the Appalachian Mountains which are a mountain system located North East in the UNited States and go accross 1,500 miles in the North east territories.

sounds good to me mate!