Editing a question or a description is still editing the actual contents of the actual entity that you selected, whereas both editing the contents of a category for a random question or switching the category of a random question are both mode complicated operations conceptually.
(BTW good that you brought to my attention that the button still reads description/label - if the name of "Description" won't be changed, at least we need to stay consistent internally).
Even if If contents of random questions were no longer selected exclusively from single categories, both of these two links would still have to be there:
- a link to view that selection of questions which is being used, and to select a single question from that selection for editing its contents
- and a link to change the configuration of the random question itself, determining the criteria for selecting the questions
As a side note: Once the random question is already in the quiz, it seems to me the primary, simple operation to edit the contents of that random question, to go inside that random question. If the user interface offers the flexibility going back in the workflow of changing the criteria of how to select the questions into the random question (undoing a selection made earlier), that is all good and well, but that seems to me not editing the random question but switching its essence, i.e. it is just as natural to just delete the random question and add another one.
In any case, I suspect adding an edit icon to only one of these related operations will potentially mislead users to think it is the other one of these operations, potentially getting them lost/confused. It seems to me that whether users associate the edit icon to editing the contents like I do, or to changing the criteria, like I guess you do, there is in any case a penalty that users get confused/lost repeatedly, since learning out from such an association can be hard.
And in any case, the link for entering the settings screen has to have some kind of a label to make its function clearer. I would suggest "configure this question" or similar.
Current thought: Add a "edit random question settings" or "edit settings" link inside the Grade box of the random question.