This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vitamins and Nutritional Deficiencies, Subject name: Social & Preventive Medicine
[{'content': 'Best test to detect iron deficiency in community is: \nSelect and explain. \nA. Serum transferrin, B. Serum ferritin, C. Serum iron, D. Hemoglobin', 'role': 'user'}, {'content': "Answer: B \nExplanation: Evaluation of iron status in the body can be done by: Serum ferritin: 'Most sensitive tool for evaluation of iron status' , especially in populations with low prevalence of anemia. Hemoglobin concentration: A relatively insensitive index of nutrient depletion. Serum iron concentration: Normal range is 0.80 - 1.80 mg/L. Serum transferrin saturation: Normal value is 30%.", 'role': 'assistant'}]