Question: Who is the youtube that has most subscribers?
Disambiguated questions and answers: question: Who became the YouTube channel with the most subscribers on Dec 23, 2013?
Who became the YouTube channel with the most subscribers on Dec 12, 2013?
Who became the YouTube channel with the most subscribers on Dec 8, 2013?
answer: PewDiePie
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PewDiePie
Natural Questions answer: PewDiePie (from the Wikipedia article "List of most-subscribed YouTube channels")