Henoch - Schonlein purpura is characterized by the deposition of the following immunoglobulin around the vessels :

Answer is C (IgA): The presumptive pathogenic mechanism for Henoch-Schonlein purpura is immune complex deposition on endothelium of blood vessels throughout the body and within glomerular mesangial regions. IgA is the antibody class most often seen in the immune complexes and has been demonstrated in the renal biopsies of these patients' - Harrison.