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: Medicine
[{'content': 'Which one of the following is the most appropriate clinical tests to confirm the iron-deficiency anaemia? \nSelect and explain. \nA. Red blood cell indices, B. Serum ferritin level, C. Bone-marrow examination, D. Urinary iron clearance', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]