This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vasculitis, Subject name: Medicine
[{'content': "Wegener's granulomatosis is diagnosed by: \nSelect and explain. \nA. P-ANCA, B. c-ANCA, C. m-ANCA, D. A.N.A", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (b) c-ANCARef.:Harrison 18th edition, Chapter 326:* c- ANCA= Wegener granulomatosis/Granulomatosis with angitis* p-ANCA# Microscopic polyangitis# Primary sclerosing cholangitis# Churg strauss syndromeThe terminology of cytoplasmic ANCA (cANCA) refers to the diffuse, granular cytoplasmic staining pattern observed by immunofluorescence microscopy when serum antibodies bind to indicator neutrophils. Proteinase-3, a 29-kDa neutral serine proteinase present in neutrophil azurophilic granules, is the major cANCA antigen.', 'role': 'assistant'}]