When BitTorrent bought over μTorrent, they promised users that all adverts would be optional. They have, however, made it harder and harder to hide the adverts including now a set of hidden options. Thankfully users have found how to access those hidden options.
Turn off ALL Ads/Featured Content/Bundle Crap in μtorrent/Bittorrent:
Options > Preferences > Advanced
Turn ALL settings to false:
Options > Preferences > Hold Shift+F2 while clicking Advanced (Hidden fields)