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
Major constituent of surfactant is - 
Select and explain. 
A. Dipalmitoyl lecithine, B. Dipalmitoyl cephaline, C. Dipalmitoyl serine, D. Dipalmitoyl inositol
A: Dipalmitoyl lecithine
Answer: A: Dipalmitoyl lecithine 
Explanation: Ans. is 'a' i.e., Dipalmitoyl lecithin o The major (65%) constituent of surfactant is dipalmitoylphosphatidylcholine (dipalmitoyl-lecithin); which is a phospholipid.