Question: The Campbell and Kelly Building is located in what Nevada county?

Context paragraphs:
Kingvale, California: Kingvale is a census-designated place (CDP) in Placer County and Nevada County, California, United States.  The CDP straddles the border of the two counties, with Nevada County to the north and Placer County to the south.  It is located near Soda Springs, 5.5 mi west of Donner Pass.  Kingvale was listed on an official map as of 1955.  The population was 143 at the 2010 census.

Doris Foley Library for Historical Research: The Doris Foley Library for Historical Research (formerly, Nevada City Free Public Library and Nevada City Library; colloquially: Carnegie Library or Foley) is a reference and research library in Nevada City, in Nevada County, California.  Built in 1907, the Romanesque Revival style building is currently a branch of the Nevada County Library System.

Tonopah, Nevada: Tonopah is an unincorporated town in and the county seat of Nye County, Nevada, United States.  It is located at the junction of U.S. Routes 6 and 95, approximately midway between Las Vegas and Reno.  In the 2010 census, the population was 2,478.  The census-designated place (CDP) of Tonopah has a total area of 16.2 sqmi , all land.

Nevada County Narrow Gauge Railroad: The Nevada County Narrow Gauge Railroad (NCNGRR) (nickname: "Never Come, Never Go") was located in Northern California's Nevada County and Placer County, where it connected with the Central Pacific Railroad.  The Nevada County Narrow Gauge Railroad Company incorporated on April 4, 1874, and was headquartered in Grass Valley, California.  After two years of construction, passenger and commercial rail services began in 1876 and continued until 1943.  The 22.53 mi line ran from Colfax, north through Grass Valley to Nevada City.  At one time, the railroad was notable for having the highest railroad bridge in California, the Bear River Bridge, built in 1908.

Kres, California: Kres is an unincorporated community in Nevada County, California.  It lies at an elevation of 2861 feet (872 m).  Kres is located on the Nevada County Narrow Gauge Railroad, 3 mi east-southeast of Grass Valley.

Nevada County Air Park: Nevada County Air Park (ICAO: KGOO) is a county-owned public use airport in Nevada County, California, United States.  The airport is located three nautical miles (6 km) east of the central business district of Grass Valley, California.  It is also known as Nevada County Airport.

Coleman, California: Coleman is an unincorporated community in Nevada County, California.  It lies at an elevation of 2549 feet (777 m).  Coleman is located on the Nevada County Narrow Gauge Railroad, 2 mi north of Chicago Park.

Pinecrest, Nevada County, California: Pinecrest is an unincorporated community in Nevada County, California.  It lies at an elevation of 2438 feet (743 m).  Pinecrest is located on the Nevada County Narrow Gauge Railroad, 1 mi north of Chicago Park.

Nevada County, Arkansas: Nevada County is a county located in the U.S. state of Arkansas.  As of the 2010 census, the population was 8,997.  The county seat is Prescott.  Nevada County is Arkansas's 63rd county, formed on March 20, 1871, from portions of Hempstead, Ouachita and Columbia Counties.  It was named after the state of Nevada because of the perceived similarity between their physical shapes; the Arkansas county's shape roughly follows the same outline as the state's boundary when inverted.  In contrast with the name of the state, the local pronunciation for the southwestern Arkansas county is "nuh-VAY-duh".  It is an alcohol prohibition or dry county.

Campbell and Kelly Building: The Campbell and Kelly Building, at Corona and Main Sts.  in Tonopah, Nevada, is a historic building built c. 1912.  It was listed on the National Register of Historic Places in 1982.

Supporting paragraphs: Campbell and Kelly Building Tonopah, Nevada
Answer: Nye County