<prompt> C- ANCA positivity indicates, antibody formed against which of the following?Proteinase 3MyeloperoxidaseCytoplasmic antinuclear AntibodyAnti centromere Antibody  <response>: C-ANCAs Cytoplasmic anti-neutrophil cytoplasmic antibodies, are a type of autoantibody formed against proteinase 3. P-ANCA Perinuclearanti-neutrophil cytoplasmic antibodies are antibodies directed against myeloperoxidase. Ref: Harrisons Principles of Internal Medicine, 16th Edition, Page 2002; Thurlbecks Pathology Of The Lung, William M. Thurlbeck, 3rd Edition, Page 372; Rheumatology Secrets, Sterling G. West, 2nd Edition, Page 226. 