There is an option to create dynamic ads in Facebook.  You add several images and text options and Facebook evaluates and shows the best performing combinations.

Pros: Facebook does the analysis for you to optimize. You can see how each part contributed.

Cons: You give up much of the control over testing.

Takeaway:  This is a great option for a mid-length/mid-budget campaigns where there isn’t time available to evaluate and adjust manually.  It may not be better for larger, longer, ongoing campaigns where you will want to have more control or for very short term boosts where there is no need for additional creative.

How to find dynamic creative asset performance: https://www.facebook.com/help/publisher/176286959893814