There is one universal fact of the world: When people are by themselves at home or getting dressed to go out, they dance around to pop music in their underwear.
Tom Cruise did it in Risky Business to the hit "Old Time Rock and Roll," Cameron Diaz did it in Charlie's Angels while listening to "Heaven Must Be Missing an Angel," and Niall Horan from One Direction apparently does it while listening to Taylor Swift's "Shake It Off."
ET's Rocsi Diaz caught up with the guys of One Direction on the red carpet at the 2014 American Music Awards – before their wildly successful night - and asked them the question that really matters.
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After Rocsi admitted that she dances in her underwear to the records of One Direction, she asked the guys who they listen to while rocking out in their boxers.
"'Shake It Off'," answered Niall, without any hesitation.
Wow, Liam Payne nailed it when he followed up Niall's admission with, "That's controversial."
As it turns out, it looks like Niall's bandmate Harry Styles and pop diva Taylor Swift might be rekindling the romance, after their previous relationship allegedly inspired some of Taylor's best-selling songs off her new album 1989.
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So what did Harry have to stay about the song?
"It's a great song," Harry said with a smile. He's a man of few words.
"Shake It Off" isn't their only guilty pleasure -- apparently the boys of 1D also like to indulge in the occasional rom-com. In another interview on the red carpet, the guys gave a delightful reference to the comedy classic When Harry Met Sally.
Check out the video for more from One Direction, including each of the band members weighing in on the debate of the century: Which sexy song is better, "Bang Bang" or "Booty"? Their choices may surprise you.