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: Medicine
Most common extra articular manifestation seen in Ankylosing spondylitis 
Select and explain. 
A. Anterior uveitis, B. Keratitis, C. Amyloidosis, D. Upper lobe pulmonary fibrosis
A: Anterior uveitis
Answer: A: Anterior uveitis 
Explanation: M/C extra articular manifestation - Acute anterior uveitis.