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 of the following is a characteristic feature of hypoproliferative anemia ? \nSelect and explain. \nA. Normocytic normochromic anemia with reticulocyte index < 2-2.5, B. Microcytic hypochromic anemia with reticulocyte index < 2-2.5, C. Microcytic hypochromic anemia with reticulocyte index > 2-2.5, D. Microcytic anemia with ringed sideroblasts', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Anemias associated with normocytic and normochromic red cells and reticulocyte index (< 2-2.5) are hypoproliferative anemias. Reference: Harrisons Principles of Internal Medicine, 18th Edition, Page 844', 'role': 'assistant'}]