Versions A and C have other navigation/messaging in the spotlight. Version B has the fewest distractions.
Poor illustration of the point, if you ask me.
This is like assuming your users are stupid. Strive for accessibility and ease of use, not ugliness.
But the closing statement in that paragraph is:
"It’s no surprise that the winning test lacks design elements or complexity, keeping it simple collects the sale."
So ultimately, I think we're all on the same page.
Simple & clear messaging trumps complexity.
I found this article to have better examples. In particular, the ChristianMingle ad -- same wording, different treatment, different results.
However since they offer a competitive product at very competitive prices people put up with horrible usability and service. So no, ugly design doesn't sell, cheap sells, and if you're cheap enough people are willing to overlook ugly.