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': 'Hair on end appearance is seen in X-ray skull in \nSelect and explain. \nA. Thalassemia, B. Hydrocephalus, C. Chronic malaria, D. Sickle cell analuria', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]