You can edit your quiz in these easy steps below:
1. Click on the Commerce tab on the left and scroll to Courses.
2. Click on the course that has the quiz you want to modify.
3. Click on the Curriculum tab and then select the quiz you want to modify.
4. Click on the edit button for that quiz on the right.
5. Add or remove an option, make modifications.
6. Click Update Question button below.