Q：The function of the lock icon in the Video Quiz

A：The lock icon can be used to enable or disable quiz creation.

      When the lock is enabled, it allows teachers to easily edit quizzes with the following features:

• Freely move the video progress bar
• Previously created quiz questions will be indicated by red dots on the progress bar
• Clicking on the red dots allows you to edit the quiz questions again
• Previously created quiz questions will not be displayed during playback