In the event dashboard, click on "Content" from the sidebar. 

Now click on the “Agenda” page, which lists all the sessions added to the event.

Click on the "Edit" option in the desired session on the session card. 

You will now see all details about the session. Click on the “Questions” tab on the left-hand side under session details. 

Now click on the “Approve” button if you want this question displayed in the session. 

How to approve and hide questions in a moderated Q & A?