Britney is the perfect choice to mentor the teens because she's been in their shoes.
Simon's unique experience shepherding bands such as One Direction makes him the ideal mentor.
Despite not wanting to mentor the Over 25s at first, LA is ready for the challenge.
Demi's group is thrilled to have her as their mentor.
The X Factor sneak peek.
X-Factor interviews with Xfinity TV
X Factor sneak peek
X-Factor sneak peek
X factor sneak peek.
Sneak peek of The X Factor
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