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 - B27 is associated with - \nSelect and explain. \nA. Ankylosing spondylitis, B. Rheumatoid arthritis, C. Chronic active hepatitis, D. Diabetes', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A variety of diseases have been found to be associated with certain HLA alleles.\nThe best know is the association of HLA-B27 with ankylosing spondylitis (AS), individuals who inherit this allele have a 90 fold greater chance of developing AS than those who are negative for HLA - B27.', 'role': 'assistant'}]