So many things can be photo enhanced and altered. Scenario: If someone had to prove to me who they were...what should I ask for as a photo?

It depends on the situation. Are they trying to get personal information from you or are they trying to reconnect with you as a friend? If they are looking for personal information, I wouldn't trust a thing they say. If they are looking to reconnect as a friend, a simple photo would do great. After all, that is the basis for Facebook and other social media. Best of luck to you!