In the southern campaign launched by the British, Cornwallis lost a battle with American under Nathaniel Greeene at A. Charles Town B. Camden C. Savannah D. Cowpens

I choose A

2 answers

I think you mean Cowpens which was Greene but only indirectly Cornwallis although he was in overall command of that British army.
If you mean Charlestown (Bunker Hill), no way