Which geographic feature did the british government use in 1763 as a boundary to restrict the westward settlement of american colonists?
(1)st. lawrence river
(2)rocky mountains
(3)appalachian mountains
(4)mississippi river

3) Appalachian Mountains

Explanation:

After the Seven Years War (also known as the French and Indian War in America) the British won a large piece of land that used to belong to the French.  This land extended all the way from the Appalachian Mountains to the Mississippi River.  Technically this land could've now been used by American colonists because it now belonged to Britain, and they felt they had a right to use it since they had helped the British win the war.  The British did not agree and the king made a statement called the Proclamation of 1763 that said that expansion west of the Appalachian Mountains was forbidden.  This Proclamation angered the colonists.