This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Medicine
[{'content': "Triplet repeat is seen in all EXCEPT \nSelect and explain. \nA. Fragile-x syndrome, B. Huntington's disease, C. Friedreich's ataxia, D. Cystic fibrosis", 'role': 'user'}, {'content': 'Answer: D \nExplanation: (D) Cystic fibrosis', 'role': 'assistant'}]