This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunity, Subject name: Pathology
HLA B-27 has > 90% association with? 
Select and explain. 
A. Enteropathic, B. Reactive arthritis, C. Rheumatoid arthritis, D. Ankylosing spondylitis
D: Ankylosing spondylitis
Answer: D: Ankylosing spondylitis 
Explanation: Ans. (d) Ankylosing spondylitis(Ref: Harrison 18th/chapter 325)Prevalence of HLA B27 is 90% in patients with Ankylosing Spondylitis, independent of disease severity.