The saved "Favorites" you're seeing in the C drive are generally those items saved for Internet Explorer. It's not a hidden folder and easy to located. Delete them from within Internet Explorer or from the C drive location and they'll be removed from IE only. (On this Windows 10 computer, the Favorites folder is located at C:\Users\username|Favorites.

On the other hand, I believe Chrome saves it's bookmarks on the C drive at a different location, : "AppData\Local\Google\Chrome\User Data\Default." and the "AppData" folder is a hidden folder which you'll have to "unhide" in the Folder Options/File Explorer Options section of the Control Panel to see the various bookmark listings.

Hope this helps.

Grif