By Daily Mail Reporter
Her final teen contestant skated through to the finals on Thursday night's X Factor.
But as Britney Spears was gritting her teeth before Carly Rose Sonenclar's name was called, all eyes were on her daring look for the television singing competition.
The 31-year-old pop star harkened back to her hey-day in a plunging sheer paneled mini-dress that showed off her slim waist and toned legs.
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The Toxic singer, whose own music career has taken a backseat while she mentors contestants on the programme, wore her blonde hair curled around her shoulders and pulled off her face.
Walking on stage joined by Simon Cowell, Demi Lovato and L.A. Reid, she waved to the crowd shyly and the evening's elimination results rang in.
Britney was visibly stunned and admitted she was not particularly happy with the way the public had voted.
While Carly made it through to the finals, the star made it known she was upset when Cowell's girl group Fifth Harmony - namely Dinah Hansen, Lauren Jauregui, Ally Brooke, Normani Hamilton and Camila Cabello – were voted through, leaving boy band favourite Emblem3 to bite the dust.
Emblem3 were sent home after receiving the fewest number of public votes, meaning country singer Tate Stevens and 13-year-old schoolgirl Carly will battle it out against Fifth Harmony in next week’s live final.
Carly, standing next to Britney, was relieved when co-hosts Khloe Kardashian and Mario Lopez said she had made it though.
'I don’t even know what to say,' she stuttered tearfully. 'Thank you so much for voting, it means the world to me.'
Emblem3, meanwhile, were gracious in defeat and promised their fans they hadn’t heard the last of them.
'I’m just so honoured to have gone through this experience,' Wesley Stromberg said.
Viewers were also entertained by Bruno Mars, who sang Locked Out Of Heaven, and Bridgit Mendler, who performed her single Ready or Not.
Next week Carly Rose Sonenclar, Tate Stevens and Fifth Harmony will battle it out to be crowned the X Factor winner.
The act who finishes in first place will receive a $5million recording contract and have a music video produced by drinks giant Pepsi.
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