This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: obstetrics,pediatrics and geriatrics, Subject name: Social & Preventive Medicine
[{'content': 'LBW is bih wt below - \nSelect and explain. \nA. 1.5 kg, B. 2.5 kg, C. 3.0 kg, D. 3.5 kg', 'role': 'user'}, {'content': 'Answer: B \nExplanation: question repeated', 'role': 'assistant'}]