The following are multiple choice questions (with answers) about medical knowledge.   **Question:** A 79-year-old man presents to the office due to shortness of breath with moderate exertion and a slightly productive cough. He has a medical history of 25 years of heavy smoking. His vitals include: heart rate 89/min, respiratory rate 27/min, and blood pressure 120/90 mm Hg. The physical exam shows increased resonance to percussion, decreased breath sounds, and crackles at the lung base. Chest radiography shows signs of pulmonary hyperinflation. Spirometry shows a forced expiratory volume in the first second (FEV1) of 48%, a forced vital capacity (FVC) of 85%, and an FEV1/FVC ratio of 56%. According to these results, what is the most likely diagnosis?   (A) Asthma   (B) Lymphangioleiomyomatosis   (C) Chronic obstructive pulmonary disease (COPD)   (D) Heart failure
['(C) Chronic obstructive pulmonary disease (COPD) <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Asthma \n (B) Lymphangioleiomyomatosis \n (C) Chronic obstructive pulmonary disease (COPD) \n (D) Heart failure <> possible answers', '  A 79-year-old man presents to the office due to shortness of breath with moderate exertion and a slightly productive cough. He has a medical history of 25 years of heavy smoking. His vitals include: heart rate 89/min, respiratory rate 27/min, and blood pressure 120/90 mm Hg. The physical exam shows increased resonance to percussion, decreased breath sounds, and crackles at the lung base. Chest radiography shows signs of pulmonary hyperinflation. Spirometry shows a forced expiratory volume in the first second (FEV1) of 48%, a forced vital capacity (FVC) of 85%, and an FEV1/FVC ratio of 56%. According to these results, what is the most likely diagnosis? <> context@']