This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Blood, Subject name: Medicine
[{'content': 'A 32-year-old man has a mild anemia diagnosed on routine testing. He has no symptoms and feels fine. His clinical examination is normal, and a blood film reveals some target cells with some red cells having intraerythrocytic crystals.For the above patient with a hemoglobin abnormality, select the most likely diagnosis. \nSelect and explain. \nA. beta-thalassemia major, B. HbH disease, C. sickle cell disease, D. HbC disease', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The patients with homozygous HbC disease have mild hemolysis, splenomegaly, target cells, and HbC crystals. Unlike sickle cell disease, the prognosis is favorable.', 'role': 'assistant'}]