Check boxes mean that there are possibly more than 1 correct answer and you need to select all of them. It's no better or worse than Microsoft certifications with multiple choice questions where multiple answers may be correct.
I hate to spill the beans (Steve, wipe this out if you want), but if you see checkboxes on the QOD it always means there is more than one answer. When you put in a QOD, you check the answers that are correct. If you pick only one as correct, it displays radio buttons. If you pick multiple, it will use check boxes. So... if you see check boxes, always select at least two answers...
🙂
Chad