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': 'Stability of alveoli is maintained by? \nSelect and explain. \nA. Lung compliance, B. Negative intrapleural pressure, C. Increase in alveolar surface area by the surfactant, D. Residual air in alveoli', 'role': 'user'}, {'content': 'Answer: C \nExplanation: C i.e. Increase in alveolar surface area by the surfactant', 'role': 'assistant'}]