If you explore Final Fantasy 7 Rebirth's Corel Prison enough, you'll come across Conniving Caglio and his merry band of con artists. You'll find out who's telling the truth, because spoilers, there's no one answer!
Who's Telling the Truth (Swindling Seminar Quest) in FF7 Rebirth
Swindler's Seminar is a Swindler's game. Truth is random. There will always be five statements, but only one of them will be true. Here is a list of all the correct facts and answers for every topic in town.
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Your task now is to see which of the students has one of the above answers. Don't waste your 500 Gil like I did! Caglio will reward you with some green for your efforts.