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': 'The kind of hypoxia seen in the collapse of lungs and depression of respiratory centre is: \nSelect and explain. \nA. Hypoxic hypoxia., B. Anaemic hypoxia., C. Stagnant hypoxia., D. Histotoxic hypoxia.', 'role': 'user'}, {'content': 'Answer: A \nExplanation: In this condition oxygen therapy is useful.', 'role': 'assistant'}]