A62-year-old construction worker presents to the clinic reporting almost a chronic cough and occasional shortness of breath that have lasted for almost 1 year. although symptoms have occasionally worsened with a cold, they have stayed about the same. the cough has occasional mucus drainage but never any blood. he denies any chest pain. he has had no weight gain, weight loss, fever, or night sweats. his past medical history is significant for high blood pressure and arthritis. he has smoked two packs a day for the past 45 years. he drinks occasionally but denies any illegal drug use. he is married with two children. he denies any foreign travel. his father died of a heart attack and his mother died of alzheimer's disease. examination reveals a man looking slightly older than his stated age. his blood pressure is 130/80 and his pulse is 88. he is breathing comfortably with respirations of 12. his head, eyes, ears, nose, and throat examinations are unremarkable. his cardiac examination is normal. on examination of his chest, the diameter seems enlarged. breath sounds are decreased throughout all lobes. rhonchi are heard over all lung fields. there is no area of dullness and no increased or decreased fremitus. what thorax or lung disorder is most likely causing his symptoms?