This fortress- in what is now pittsburgh- was a major battle site in the seven years war/french and indian war, and a major victory for the british.

The correct answer is Fort Duquesne. At first the French controlled it and the British attacked to take it from them. The french withdrew and destroyed the fort when they realized the British were going to win and this became a major victory for the British army.

Your answer would be a in this question good luck