This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Musculoskeletal Radiology, Subject name: Radiology
Flowing wax appearance on anterior borders of veebrae is seen in- 
Select and explain. 
A. Ankylosing spondylitis, B. DISH, C. Psoriatic ahropathy, D. Rheumatoid ahritis
B: DISH
Answer: B: DISH 
Explanation: Calcification of Anterior longitudinal ligament- DISH; Diffuse Idiopathic skeletal hyper osteosis Calcification of posterior longitudinal ligament -OPLL: Ossified posterior longitudinal ligament - JAPAN: Disease Ossification / calcification of interosseous membrane - FLUOROSIS