This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pathology
[{'content': 'All of the following immunodeficiency diseases are due to Chromosomal instability or defective repair of genes except \nSelect and explain. \nA. Ataxia telangiectasia, B. Bloom syndrome, C. Seckel syndrome, D. Chediak - Hegashi syndrome', 'role': 'user'}, {'content': 'Answer: D \nExplanation: .', 'role': 'assistant'}]