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': 'Siblings of the diagnosed patient with Wilson disease will be having what risk of Wilson disease? \nSelect and explain. \nA. 25%, B. 50%, C. 75%, D. 100%', 'role': 'user'}, {'content': "Answer: A \nExplanation: The frequency of Wilson's disease in most populations is about 1 in 30,000. Siblings of a diagnosed patient have a 1 in 4 risk of Wilson's disease. Reference: Harrisons Principles of Internal Medicine, 18th Edition, Page 3188", 'role': 'assistant'}]