This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Pathology
[{'content': 'Response to iron in iron deficiency anemia is denoted by - \nSelect and explain. \nA. Restoration of enzymes, B. Reticulocytosis, C. Increase in iron binding capacity, D. Increase in hemoglobin', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Oral iron therapy is continued long enough both to correct anaemia and to replenish the body iron stores. The response to oral iron therapy is observed by reticulocytosis which begins to appear in 3-4 days with a peak in about 10 days. References: Textbook of Pathology Seventh edition Author: Harsh Mohan Page No.276', 'role': 'assistant'}]