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: Physiology
[{'content': 'Administration of pure O2 to hypoxic patients is dangerous because \nSelect and explain. \nA. Apnea occurs due to hypostimulation of peripheral chemoreceptors, B. Pulmonary edema, C. DPG, D. Convulsions', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The respiratory centres maybe depressed in hypercapnic patients. Breathing may only be occurring due to the activation of peripheral chemoreceptors sensitive to the hypoxia. When pure Oxygen is given to the patients, the stimulus to the peripheral receptors is gone and may result in apnoea.', 'role': 'assistant'}]