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: Pathology
[{'content': "The best method for hemoglobin estimation is - \nSelect and explain. \nA. Sahli's hemoglobinometer, B. Cyanmethemoglobin method, C. Calorimetric method, D. None of the above", 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]