I do quizzes in mentimeter every sunday since 6 years. I create 50 questions ("select answer") with 4 alternative answers. After creating the quiz I try to check all the questions to make sure I haven't made any mistakes. Despite that I always miss to check the correct answer on at least one question and get boos and laughs from the crowd.

A feature that would really help -and save time every week- is if there was an icon (in the list of questions on the left side) that shows if there isn't a correct answer selected. Then I wouldn't have to open every question to check it, I could just scroll the list.

When you added the possibility to see in the list when there is a picture in a question helped a lot. The feature I suggest is even more important in my opinion.