We have 2 forms, one form with quiz questions and answers and another form that uses the data from form 1 and allows users to write their own answers, to answer the quiz

Answer field is set to be restricted (view) only to users from confluence-administrators security group

Quiz for user:

This is the UI visible by quiz admin (with answers) Correct answer is taken from "quiz" form using smart field reference (quiz.answer)

So, basically the idea is that you create 2 forms - one with a quiz and another one with answers that you r users will record

And connect the forms via the Smart fields

Storage format for complete solution: