This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cystic fibrosis & Sleep apnea, Subject name: Medicine
[{'content': 'Which is not true of obstructive sleep apnea? \nSelect and explain. \nA. Nocturnal asphyxia, B. Alcoholism is a cofactor, C. Prone to hypeension, D. Spirometry is diagnostic', 'role': 'user'}, {'content': 'Answer: D \nExplanation: An overnight sleep study, or polysomnography, is required to diagnose OSA. PSG: in-laboratory measurement of sleep architecture and EEG arousals, eye movements, oximetry, snoring, and leg movements OSAHS raises 24-h mean blood pressure.', 'role': 'assistant'}]