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: Gynaecology & Obstetrics
[{'content': 'Life span of neonatal RBC is : \nSelect and explain. \nA. 120 days, B. 100 days, C. 6 months, D. One year', 'role': 'user'}, {'content': 'Answer: B \nExplanation: 100 days', 'role': 'assistant'}]