Which American general was killed during the 1945 Battle of Okinawa, making him the highest ranking U.S service member to be killed in action during WWII?

Which American general was killed during the 1945 Battle of Okinawa, making him the highest ranking U.S service member to be killed in action during WWII?

General Gustav J. Braun, Jr.
Brig. Gen. James Leo Dalton II
Brig. Gen. Charles L. Keerans, Jr.
Simon Bolivar Buckner Jr.
Maj. Gen. Maurice Rose

Answer: The correct answer is Simon Bolivar Buckner Jr..