Function to get questions/answers for quizes

I am trying to create some email notifications which break down all of the questions a quiz taker got wrong and what their answer was for each of those questions. I wrote an override for hook_quiz_finished() which gives me the quiz, the score (summary) and ID of the results. The variables passed in give me the question IDs, but not the corresponding user answers. Is there an easy function for querying this or do I have to figure it out from the SQL tables? Can someone help me understand how to retrieve that data?

Thanks so much!