Tracking the traffic sources of your users will help you to optimize your campaigns!
You can do so in Opinion Stage by adding the following to your item links. This feature is available for Quizzes, Polls, Surveys,Forms, and Slideshows.
os_utm_source=facebook (This example is for Facebook)
os_utm_source=adwords (This example is for Google Ads)
You can then go to View Statistics and export your leads to a CSV or XLSX file. Each submission in the report will contain the os_utm_source value.