While there isn’t a built-in A/B test functionality if you’d like to do something like create two different banner ads under the same advertiser for the same campaign and see which one has a better click-through-rate, there is a manual way you can do this.
Your best option would be to place both ads in the same campaign and target them to the same zones. Over time one ad will probably receive more clicks and engagement.
You can check on the individual ad stats by going to the advertiser page in our dashboard, and clicking “Reporting” on the top right.
From there you can choose which ad is performing the best and remove the lesser performing ad.