Managing a question bank

For example, when you imported questions they were not only put into a single quiz but also were entered into a question bank. If you go to Quizzes, then click on the gear symbol on the upper right (as shown in the figure) - then select Manage Question Banks - now you can manipulate the question bank.

If you are going to make changes to the questions, add figures, etc. - I would first add the changes, pictures, … to the questions in the question bank and then start to make quizzes using these questions.