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: Pathology
[{'content': 'HLA antigen is located at \nSelect and explain. \nA. Short arm of chr-6, B. Long arm of chr-6, C. Short arm of chr-8, D. Long arm of chr-8', 'role': 'user'}, {'content': 'Answer: A \nExplanation: HLA complex (MHC) gene is located on the short arm of chromosome 6.', 'role': 'assistant'}]