Multiple answer question only displays two choices

I am having difficulties adding more than 2 answers on a multiple choice question.
when I add extra answers and clicking save, the answers list reverts to two entries and the second answer is changed to whatever the last input answer was.

I have granted access to my site. The problem is in the only course I have made thus far. It contains a final exam as the last unit. The issue is questions #26-28 on that final exam. Strangely, question 4 is also multiple-choice and successfully displays all 6 choices.