User blog:Zuragonium/Can you solve this riddle?

Aen asked 3 prisoners in US independent day of 2017.

Their names was X,Y and Z.

Aen asked "What did you do yesterday?"

X said "I was exposing alts."

Y said "I was busy with so many homeworks"

Z said "I was commenting on YouTube"

Who created the alt?

Note; This is justg a riddle,so this is not real happenings in Mapperdonia.