If you have the proper roles in the system, Administrator, you are able to delete a Question Set.
You will know if you have the proper role if you see this button on your Question Set.
If you don't see that button you can't delete a Question Set. You will need to contact your company's OpsAnalitica Admin to get that role or to delete it for you.
Here is a quick explanation of the two Delete Question Set Options:
If you select:
Responses: you will delete all the completed checklists and schedules for this Question Set. You are clearing out the existing data without deleting the actual checklist.
Question Set: You delete all completed checklists, all schedules and the checklist. Basically it will be like this checklist never existed.