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': 'What can be the non-respiratory functions of lungs: \nSelect and explain. \nA. Sodium balance., B. Fibrinolytic function., C. Secretion of heparin., D. All of the above.', 'role': 'user'}, {'content': 'Answer: D \nExplanation: NON respiratory function of lung: \n\nACE synthesized by lung – Na balance. \nFibrinolytic function – Pulmonary Endothelium is rich in PLASMIN activator. \nHeparin – Lung is rich in mast cells which secrete heparin. \nSURFACTANT – Synthesized by type 2 alveolar epithelial cells.', 'role': 'assistant'}]