츄~♥ (aka Chu~♡) was released on f(x)'s first single album of the same name and later released on their repackage album, Hot Summer. The single charted at #3 and sold 20,000 physical copies.
I'm surprised that it's between 2NE1 & T-ara. I would have swear it would have been 2NE1 vs. SNSD or BEG vs F(x). I would have never guessed that SISTAR would have lost that many songs already.
