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': 'A ventilator pressure relief valve stuck in closed position can result in - \nSelect and explain. \nA. Barotrauma, B. Hypoventilation, C. Hypoxia, D. Hyperventilation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]