Concept:The word "fast" can function as both an adjective and an adverb without changing form.Explanation:The sentence requires an adverb to describe how she hurried."Fast" already works as an adverb, so no extra suffix is needed."Fastly" is not a standard English word.Options A, B, and D are therefore incorrect.The correct adverb is simply "fast."Correct option: C. fastAnswer:C. fast