<prompt> A 67-year-old woman has pulmonary function tests performed to evaluate symptoms of dyspnea. The most prominent finding is a reduction of the ratio of FEV1FVC. Which of the following is the most likely diagnosis?COPDankylosing spondylitisPickwickian syndromescleroderma of the chest wall  <response>: The VC is reduced in emphysema, but the FEV1 is grossly reduced because of high airway resistance. In predominant emphysema, diffusing capacity is more profoundly decreased than in predominant bronchitis. 