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: Medicine
[{'content': 'Value of Pa02/ Fi02 chracteristic of ARDS is \nSelect and explain. \nA. < 200 mmHg, B. 200 - 400 mmHg, C. 400 - 600 mmHg, D. 600 - 800 mmHg', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Answer- A. < 200 mmHgAcute respiratory distress syndrome (ARDS) is a clinical symdrome of severe dyspnea of rapid onset, hypoxemia, and diffirse pulmonary infiltrates leading to respiratory failure.The aerial PaO, (in mmHg)/FiO, (inspiratory O, fraction) <200 mmHg is characteristic of ARDS, while a PaO, /FiO, between 200 and 300 identifies patients with ALI who are likely to benefit from aggressive therapy.', 'role': 'assistant'}]