Hey there! I'm happy to help!
The battle of Lexington was a small battle fought against the Hessians in New Jersey. Lexington wasn't really against the British army. It was a victory, but not a turning point.
Yorktown was the end of the revolution, so it's not a turning point.
Duquesne wasn't during the revolution but it was during the French and Indian war. It was a fort in present day Pittsburgh.
The Battle of Saratoga was the U.S.'s first defeat of the British army by themselves. This was very empowering and gave them more hope in the revolution.
Therefore, the answer is A) Saratoga.
I hope that this helps! Have a wonderful day!
