Atwenty-one-year-old female presents to your clinic complaining of shortness of breath and a nonproductive nocturnal cough. she states she used to feel this way only with extreme exercise, but lately, she has felt this way continuously. she denies any other upper respiratory symptoms, chest pain, gastrointestinal symptoms, or urinary tract symptoms. her past medical history is significant only for seasonal allergies, for which she takes a nasal steroid spray but is otherwise on no other medications. she has had no surgeries. her mother has allergies and eczema, and her father has high blood pressure. she is the only child. she denies smoking and illegal drug use but drinks three to four alcoholic beverages per weekend. on examination, she is in no acute distress and her vital signs are: t 98.6, bp 120/80, pulse 80, and respirations 20. her head, eyes, ears, nose, and throat examinations are essentially normal. inspection of her anterior and posterior chest shows no abnormalities. on auscultation of her chest, there is decreased air movement and high-pitched whistling on expiration in all lobes. percussion reveals resonant lungs. what is your diagnosis?