I had several occurrences of an issue where in one of the multiple choice questions the correct answer becomes unchecked (in the unit creation page), and as a consequence, students do no have options to choose from.
The first time it happened, I thought I had been careless and had forgotten to set the correct answer.
For the next unit, I double-checked that all questions have the correct answer, and that in the Preview view, all questions have a list of options to choose from. Saved it afterwards. Still the next day one of the students finds that one question has no options to answer.
The third time I checked, I think, 5 times, and saved the unit as many times, and yet the next day one of the questions is without options.
Of course, human (i.e., my) error is a possibility, but even though I am not the most careful person in the world, I cannot believe that I can make the same mistake 3 times in a row after 5 verifications.
Perhaps something in my workflow causes this?
1) The titles of my questions are "Question 1", "Question 2", etc., so different units have questions with the same titles - any possibility that this causes problems?
2) I don't create questions in draft mode and then switch the unit to "Live"; instead, I create questions in the "Live" mode - this is to work around another bug reported here
Can this or something else cause questions to lose the correct answer?