This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous system, Subject name: Pediatrics
[{'content': 'Lecithin-Sphingomyelin ratio is used for \nSelect and explain. \nA. Lung maturity, B. Age of infant, C. Kidney maturity, D. Brain maturity', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Lecithin- Spingomyelin ratio is used for lung maturity. The results of this test are given as a ratio of lecithin to sphingomyelin. The range of results are: A ratio of less than 1.5:1. This means that your baby&;s lungs are immature. If born now, your baby may have breathing problems. A ratio between 1.5:1 and 1.9:1. This means that your baby may be at risk for immature lungs and breathing problems. A ratio of more than 2:1. This means that your baby has mature lungs. He or she is ready for life outside the uterus. Reference: GHAI Essential pediatrics, 8th edition', 'role': 'assistant'}]