Question: Which Air Force Base is based in Harrison County and stations the 403d Operations Group?
Context: The 690th Cyberspace Operations Group, at Lackland Air Force Base, Texas, is a United States Air Force group managing four squadrons relating to computer network operations.  The group was established 1 April 1991 as the 6900 Communications-Computer Group.  The group was redesignated the Air Intelligence Agency Intelligence Systems Group on 1 October 1993.  It was redesignated again as the 690th Information Operations Group on 1 Oct 1997.  On 5 July 2006, the group was again re-designated as the 690th Network Support Group. The 403d Operations Group (403 OG) is the operational flying component of the United States Air Force Reserve 403d Wing.  It is stationed at Keesler Air Force Base, Mississippi. Keesler Air Force Base (IATA: BIX, ICAO: KBIX, FAA LID: BIX) is a United States Air Force base located in Biloxi, a city in Harrison County, Mississippi, United States.  The base is named in honor of aviator 2d Lt Samuel Reeves Keesler, Jr., a Mississippi native killed in France during the First World War.  The base is home of Headquarters, Second Air Force (2 AF) and the 81st Training Wing (81 TW) of the Air Education and Training Command (AETC). The 731st Air Mobility Squadron (731 AMS) is an air mobility squadron of the United States Air Force based at Osan Air Base in South Korea.  It is part of the 515th Air Mobility Operations Group, based at Yokota Air Base, Japan and the 515th Air Mobility Operations Wing, based at Hickam Air Force Base, Hawaii. The 917th Air Refueling Squadron is an inactive United States Air Force unit.  It was last active as a Geographically Separated Unit at Dyess Air Force Base, Texas, while assigned to the 43d Operations Group at Malmstrom Air Force Base, Montana, where it was inactivated on 1 July 1994. The 1st Operations Group (1 OG) is the flying component of the 1st Fighter Wing, assigned to the USAF Air Combat Command.  The group is stationed at Langley Air Force Base, Virginia.  The 1st Operations Group is the oldest major air combat unit in the United States Air Force, being the successor organization of the 1st Pursuit Group.  The 1st Pursuit Group was the first air combat group formed by the Air Service, American Expeditionary Force, on 5 May 1918. A Double cantilever hangar is a type of hangar that was constructed by the United States Air Force during the Cold War.  Large hangers were constructed at Castle Air Force Base, Loring Air Force Base, Carswell Air Force Base, and Travis Air Force Base, while smaller hangars were constructed at March Air Force Base, Edwards Air Force Base, Hanscom Air Force Base, and Homestead Air Force Base. The 733d Air Mobility Squadron (733 AMS) is an air mobility squadron of the United States Air Force based at Kadena Air Base in Japan.  It is part of the 515th Air Mobility Operations Group, based at Yokota Air Base, Japan and the 515th Air Mobility Operations Wing, based at Hickam Air Force Base, Hawaii. The 730th Air Mobility Training Squadron is an Air Force reserve unit stationed at Altus Air Force Base, Oklahoma, where it trans airmen on Boeing C-17 Globemaster III, Boeing KC-135 Stratotanker and Boeing KC-46 Pegasus aircraft systems.  It is assigned to the 507th Operations Group at Tinker Air Force Base, Oklahoma, but performs its training mission under the direction of the 97th Air Mobility Wing of Air Education and Training Command. Kadena Air Base (嘉手納飛行場 , Kadena Hikōjō ) , (IATA: DNA, ICAO: RODN) is a United States Air Force base in the towns of Kadena and Chatan and the city of Okinawa, in Okinawa Prefecture, Japan.  Kadena Air Base is home to the USAF's 18th Wing, the 353d Special Operations Group, reconnaissance units, 1st Battalion, 1st Air Defense Artillery, and a variety of associated units.  Over 20,000 American servicemembers, family members, and Japanese employees live or work aboard Kadena Air Base.  It is the largest and most active US Air Force base in the Far East.
Answer: Keesler Air Force Base