This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Functional Anatomy - Respiratory System, Subject name: Physiology
[{'content': 'Major constituent of surfactant is - \nSelect and explain. \nA. Dipalmitoyl lecithine, B. Dipalmitoyl cephaline, C. Dipalmitoyl serine, D. Dipalmitoyl inositol', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Dipalmitoyl lecithin o The major (65%) constituent of surfactant is dipalmitoylphosphatidylcholine (dipalmitoyl-lecithin); which is a phospholipid.", 'role': 'assistant'}]