Answer;
Britain and France disputed borders in the Ohio River Valley.
Explanation;
-The cause of French and Indian War was the fact that the French and the English wanted to claim the land where the Allegheny, Ohio, and Monongahela Rivers meet (present-day Pittsburgh), a costly war broke out.
-Both the French and the English believed their explorers were the first to claim this land where the three rivers meet.
-Additionally, both countries wanted to keep the fur trade with the Native Americans.