Two investigative journalists have raised the question whether the new blood pressure drug, Transerythropaxil, has sensitized patients to develop fish allergies. The study was published last month in a major newspaper, and has been picked up by media throughout the country. Lab data has long shown that Transerythropaxil reacts strongly with Eicosapentaenoic acid, found in abundance in fish oil, and this reaction can produce biological irritants. Despite strenuous objections from Transerythropaxil's manufacturer, scientists working in federal labs have just published papers that provide conclusive evidence to the journalists' claim.
In the argument given, the two portions in boldface play which of the following roles?