Answer:
I just researched what HBCU is apparently all the universities you listed are supported by the HBCU, Since you have put 5 A's in your answer choice, I'm assuming it's the one you didn't mention. Please check again and let me know if these 4 state universities are the only one mentioned, or if you left one out by accident.
Boggy Depot in current Atoka County, north near Coal County line. Fought in the Choctaw Nation, 1865. Maybe.
The Appomattox Court House.