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: Microbiology
[{'content': 'HLA complex in man is located on chromosome: September 2003 \nSelect and explain. \nA. 4, B. 6, C. 8, D. 10Widal test', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B i.e. 6', 'role': 'assistant'}]