Question: What county in the 10-county Atlanta Regional Commission had a population of 259,424 during the 2010 census?
Sentence (from "Atlanta Regional Commission"): The Atlanta Regional Commission (ARC) is the regional planning and intergovernmental coordination agency for the metro Atlanta, Georgia, USA region, defined as the 10-county area of Cherokee, Clayton, Cobb, DeKalb, Douglas, Fayette, Fulton, Gwinnett, Henry and Rockdale counties, including the city of Atlanta.
Relevant evidence: Yes