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': 'Ring sideroblasts are characteristically seen in: \nSelect and explain. \nA. Myelodysplastic syndrome (MDS), B. Acute Lymphoid Leukemia (ALL), C. Acute Myeloid Leukemia (AML), D. Anemia of chronic disease', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ring sideroblasts are characteristically seen in MDS. Ref: Harrison's Principles of Internal Medicine, 16th Edition, Pages 624-25; Manual of Practical Medicine By R Alagappan, 3rd Edition, Pages 352-3", 'role': 'assistant'}]