I like Team B's chances, despite the rumors that their quarterback (what's his name? Evans? McSlappy? Something like that) will be ineligible. They have a solid running game - yeah, I know, it's gimmicky, but they averaged 215 yards a game on the ground, and their quarterback is a guy who doesn't make many mistakes (only 7 interceptions last year).
Team A is losing 7 of 11 starters on defense which wasn't very good to begin - they averaged giving up 29 points a game. Their field goal kicker was only 6 of 13 last year from beyond 30 yards, and they also lost their mascot to turf toe.
Team B will finish 11-1 and win the CCG.
Edit - The Big 12 doesn't have a CCG, stupid!