Concept:The word "sole" means one and only or exclusive.Explanation:In the sentence, "sole" shows that Morgan Pharmacy is the only distributor of the antiviral drug.The word "only" means alone in a class or group, so it has the same meaning as "sole"."Creditable" means praiseworthy, "first" means initial, and "major" means important, so these do not fit the context.Answer:B. only