The argument doesn’t discuss whether or not the press is prying into people’s personal lives. In the context of the argument, we see that many people say that the press shouldn’t pry, but the author’s argument itself doesn’t discuss whether or not the press can (or should) pry.

This is what the author presumes. The argument lays out the sufficient conditions for when the press has the right to publish stories; we don’t have the conditions to determine what the press is obligated to do. The obligation of the press is an assumption made by the author.

The argument does not make this presumption. The argument gives a conditional conclusion for when stories about private individuals are not libelous––the author isn’t presuming that these stories cannot be libelous; he’s just only talking about the stories that aren’t libelous.

This is a reversal of the assumption that the author does make. The author presumes that, if one has the right to do something, then one has the obligation to do it. (D) reverses the sufficient and necessary conditions of that relationship.

The author’s conclusion applies to stories that aren’t libelous––according to the author, the press has the obligation to publish when stories aren’t libelous (and are of interest to the public). If a story is libelous, the author’s conclusion doesn’t apply.