This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'In centrilobular (centriacinar) emphysema, there is an abnormal, permanent enlargement of the - \nSelect and explain. \nA. Respiratory bronchioles, B. Alveolar ducts, C. Small bronchi, D. Bronchioles', 'role': 'user'}, {'content': 'Answer: A \nExplanation: . Respiratory bronchioles', 'role': 'assistant'}]