In the argument above, the portions in boldface play which of the following roles? A. The first is an assertion that the author accepts as true; the second is a consideration in support of that assertion. B. The first is an assertion that the author accepts as true; the second describes a situation that the author posits as contrary to that assertion. C. The first is an assertion that the author argues against; the second is evidence presented as contrary to the author's argument. D. The first is evidence that the author believes is no longer valid; the second is additional evidence that the author uses to support his main point. E. The first is a claim that the author believes to be invalid; the second is the author's main point.