Question: The 2015 Oklahoma Sooners football team represented the University of Oklahoma in the 2015 NCAA Division I FBS football season, the 121st season of Sooner football, the team was led by which two-time Walter Camp Coach of the Year Award winner, who?
Sentence (from "2015 Oklahoma Sooners football team"): They were a charter member of the Big 12 Conference.
Relevant evidence: No