Jenny is a 19-year-old student who is undergoing a voice evaluation. Jenny complains of a gradual onset of a hoarse vocal quality and also stated that her voice "is harder to produce" (requires more effort). Jenny is a cheerleader and signs in the school choir. Jenn also often baby-sits for her two younger brothers and must raise her voice to hold their attention. Which pathological process of the vocal folds has developed or is likely to develop?