If I make a decision on a quiz but don't submit it, hit back and then next, my decision is gone

Here's the situation I'm trying to figure out:

I've got 2 slides, A and B.

Slide A is a simple info slide that shows the user a bunch of information.  It has a next button on it to get to slide B.

Slide B is a simple quiz slide that is a multiple choice quiz where I want the user to select 3 options out of ten.   It has a 'back' button on it to get to slide A as well as a submit button on it to commit the decision.

If in slide B select 2 options and then hit the back button to go Slide A  (so the user can get more background  info into how to answer the quiz question) and then hit next  from Slide A to get back to Slide B,     Slide B's questions that I had already selected are cleared out

I'd like the user's decisions to date to stay intact.. How would I do this?

Thanks in advance.