Question: Which airport Rapid City Regional Airport and Chattanooga Metropolitan Airport is closer to its local city ?

Context paragraphs:
Tennessee State Route 153: Tennessee State Route 153 (also called "Highway 153") is a state highway in Chattanooga.  It runs from Interstate 75 a few miles east of the I-75/I-24 interchange, to US 27 just south of Soddy-Daisy.  The route serves as a bypass around downtown Chattanooga for I-75 travelers heading towards US 27 North.  It is also an important route for drivers from Soddy-Daisy, Hixson, and other parts of northwestern Hamilton County who are heading for I-75 and the eastern half of the county.  It is also an important link to the TVA Chickamauga Dam, which the highway crosses on the Wilkes T. Thrasher Bridge.  It also serves as the primary access Chattanooga Metropolitan Airport.

Rapid Valley, South Dakota: Rapid Valley is a census-designated place (CDP) and unincorporated community in Pennington County, South Dakota, United States, and a suburb of Rapid City.  The population was 8,260 at the 2010 census.  Rapid Valley has been a retreat for people living in Rapid City due to its low crime, cheap land, and views of the Black Hills.  Rapid Valley is home to many industrial and financial businesses, and is the headquarters for many corporations specializing in transport and engineering.  The Rapid City Regional Airport is located in Rapid Valley.

Elizabeth City Regional Airport: Elizabeth City Regional Airport (IATA: ECG, ICAO: KECG, FAA LID: ECG) is a joint civil-military public and military use airport located three nautical miles (6 km) southeast of the central business district of Elizabeth City, in Pasquotank County, North Carolina, United States.  The airport, on the shore of the Pasquotank River, is also known as Elizabeth City-Pasquotank County Regional Airport or ECG Regional Airport.  It is included in the National Plan of Integrated Airport Systems for 2011–2015, which categorized it as a "general aviation" facility.

South Dakota Wing Civil Air Patrol: South Dakota Wing Civil Air Patrol (abbreviated as SDWG) is the highest echelon of CAP in the state of South Dakota.  The wing headquarters is at the Rapid City Regional Airport in Rapid City, South Dakota.  SDWG reports to CAP's North Central Region, which in turn reports to CAP National Headquarters at Maxwell AFB, Alabama.

Rapid City, Manitoba: Rapid City is an unincorporated community recognized as a local urban district that also once held town status in southwest Manitoba, Canada within the Rural Municipality of Oakview.  It is located about 30 km north of Brandon.  Rapid City is a farming community that is developed on the banks of the Little Saskatchewan River.  The dam and reservoir in Rapid City were built by the province in 1961, the reservoir stores 200 acre.ft and provides a water supply and recreational facility for the community.

Boyd-Buchanan School: Boyd-Buchanan School is a co-educational private Christian school located near the Chattanooga Metropolitan Airport in Chattanooga, Tennessee.  Founded in 1952, the school is a college-preparatory school for children in Pre-Kindergarten through grade 12.  Currently, the school has more than 900 students enrolled.  The school has a particularly strong affiliation with the distinctive religious beliefs of the Churches of Christ.

Dubbo City Regional Airport: Dubbo City Regional Airport (IATA: DBO, ICAO: YSDU) , is a regional airport serving Dubbo, a city in the Australian state of New South Wales.  The airport is located 2 NM northwest of Dubbo and is operated by the Dubbo City Council.  It is also known as Dubbo Airport or Dubbo City Airport.

Chattanooga Metropolitan Airport: Chattanooga Metropolitan Airport (IATA: CHA, ICAO: KCHA, FAA LID: CHA) , also known as Lovell Field, is a public airport located five miles (8 km) east of the central business district of Chattanooga, a city in Hamilton County, Tennessee, United States.  The airport is owned and operated by the Chattanooga Metropolitan Airport Authority.  It is a Class C airport serviced by Chattanooga Approach.

Rapid City Regional Airport: Rapid City Regional Airport (IATA: RAP, ICAO: KRAP, FAA LID: RAP) is a public use airport, nine miles southeast of Rapid City, in Pennington County, South Dakota.

Rocky Mountain Metropolitan Airport: Rocky Mountain Metropolitan Airport (IATA: BJC, ICAO: KBJC, FAA LID: BJC) is a public-use airport located near Broomfield, Colorado, United States.  The airport is owned and operated by Jefferson County and is situated midway between Denver and Boulder on U.S. Highway 36.  It is located sixteen miles northwest of the central business district of Denver, and is the closest airport to downtown Denver.  The airport covers 1700 acre and has three runways. Formerly known as Jefferson County Airport or Jeffco Airport, the airport was renamed Rocky Mountain Metropolitan Airport on October 10, 2006 although it is sometimes referred to as Rocky Mountain Regional Airport, e.g. 2007-2012 county planning documents.

Supporting paragraphs: Rapid City Regional Airport Chattanooga Metropolitan Airport
Answer: Chattanooga Metropolitan Airport