If you'd like to bring comments from your Facebook ad into Public Input, you'll first need to retrieve your ad's Post URL.
First, sign into your Facebook advertising account and navigate to the ad from which you'd like to retrieve comments. Click "Preview" after selecting the ad:
A new "Ad preview" interface will open. Click the dropdown menu next to ad preview, then "Facebook Post with Comments":
A new window will open with the preview of the ad post. Copy the post URL from the browser's top bar:
From here, you can paste this URL into a Facebook post. Click here for details on assigning a post URL to a question.