Creationists make up approximately half of the adults in the United States. In this video, Richard Dawkins is asked: “Do you think there could be one sentence that would convince a creationist to seriously doubt their theory?” For his answer he chooses the pattern of resemblances of genes:
While the pattern of resemblance in genes is valid answer, it is likely to go over the heads of creationists, most of whom have no real idea what a gene is or how it functions in a cell.
A more convincing answer is the utter stupidity of the “intelligent designer” if such a designer were to exist. Everyone can see this stupidity simply by reflecting on their own bodies, as described in this article:
It is shocking that anyone could look at the myriad problems in the design of the human body alone, much less in the rest of “nature”, and then propose that there is an “intelligent designer”.