This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory System, Subject name: Physiology
The principle component of surfactant that reduces surface tension in the alveoli and keeps them inflated and non-collapsed? 
Select and explain. 
A. Dipalmitoyl phosphatidylcholine, B. Phosphatidylglycerol, C. Carbohydrate component, D. Lipopolysaccharide
A: Dipalmitoyl phosphatidylcholine
Answer: A: Dipalmitoyl phosphatidylcholine 
Explanation: Ans. a (Dipalmitoyl phosphatidylcholine); (Ref. Ganong, Physiology, 21st ed., 657)SURFACTANT-- produced by type II pneumocytes,# Role--- | Alveolar surface tension,- | Compliance,- | work of inspirationApproximate Composition Of Surfactant: ComponentComposition1.Dipalmitoyl phosphatidylcholine62%2.Phosphatidylglycerol05%3.Other phospholipids10%4.Neutral lipids13%5Proteins08%6Carbohydrate02%Note: Phosphatidylcholine appears in 24th week of intrauterine life.