Forum: Rails deployment Sessions in Rails

Hello!
I'm at my very first application in Rails, and I'm learning from Agile
Development with Rails.

I'm developing a web app that is run as a questionary.
The idea is to create a database of questions (like 50), but use only
like 10-15 each session, for each user.
You can start the questionary only if you give your email
address(validatates_presence_of).

The point I'm wondering about is : since the answers are multiples and
the sessions too, how can I keep track about whose belong certains
answers? Shall I haven't a pool of mixed answers?
I was thinking about a migration with 16 slots (email, and 15 slots for
each answer), could that work? I know it's not exactly in the DRY logic,
but in this way I'll have a complete table, with which I could also
calculate how many correct answer the user did, and statistics stuff
like that.