If you want to hide a comment that has been published onto one of your lessons which has 'Public Comments' activated you can do it. You can also respond to the comment privately if you want to after it's been hidden.
On the menu inside of Analytics select 'Comments'.
Scroll down and navigate to the comment that you're looking for:
Select the 3 dot dropdown to the right of the comment. And select 'Hide' from the dropdown:
The comment will now be hidden from public view. If you want you can now respond to the comment privately. Or if you want to you can simply select 'Delete' and the comment will be removed from your account as well.