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': 'Which of the following is not component of acinus- \nSelect and explain. \nA. Pulmonary lobule, B. Respiratory bronchioles, C. Alveolar ducts, D. Alveolar sac', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Pulmonary lobule is not a component of acinus, rather cluster of 3-5 terminal bronchioles with acinus form pulmonary\xa0lobule.\n\nRespiratory tract anatomy \n\nProgressive branching of bronchi forms bronchioles.\nFurther branching of bronchioles leads to terminal bronchioles.\nTerminal bronchiole emanate into respiratory bronchioles.\nRespiratory bronchioles proceed into the alveolar ducts, with immediately branch into alveolar sacs (alveoli).\nThe part of lung distal to the terminal bronchiole is called acinus, i.e., respiratory bronchiole, alveolar duct and alveolar sac.\nA cluster of three to five terminal bronchioles, each with its appended acinus, is usually referred to as pulmonary lobule\nSo, pulmonary lobules include a cluster of three to five terminal bronchioles with its respiratory bronchioles, alveolar ducts and alveolar sacs.', 'role': 'assistant'}]