Taylor Swift Or Ariana Grande Quiz: Who Sang It?

Taylor Swift performs at Z100 Jingle Ball at Madison Square Garden, Friday, Dec. 12, 2014, in New York. (Photo by Evan Agostini/Invision/AP)
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14. "Shut Your Mouth, And If You Don't Know That Now You Know It, Babe"

Taylor Swift

Ariana Grande
Contributor

Dennis Thomas hasn't written a bio just yet, but if they had... it would appear here.