You can react to reviewer's feedback by replying to his/her comments.
In the comments pane, find the comment you want to reply to.
Click
on the right side of the comment to show available actions.
Click
on the bottom of the comment. The Reply pane (displayed below) opens.

- Enter your reply in the appropriate box (highlighted above).
Click
on the top right corner of the pane to save the reply.
If you started writing a reply to a comment but do not want to save it, you can discard the reply.
To discard a comment reply
- Click
on the top left corner of the Reply pane.