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
A 8 year old male had non blanching rashes over the shin and swelling of knee joint with haematuria +++ and protein +. Microscopic analysis of his renal biopsy specimen is most likely to show? 
Select and explain. 
A. Tubular necrosis, B. Visceral podocyte fusion, C. Mesangial deposits of IgA, D. Basement membrane thickening
C: Mesangial deposits of IgA
Answer: C: Mesangial deposits of IgA 
Explanation: Answer is C (Mesangial deposits of IgA): Presence of non blanching rash (Purpura), swelling of knee (Ahralgia) along with haematuria (glomerulonephritis) suggests the diagnosis of Henoch- Schonlein purpura. H.S purpura is characterized by deposition of IgA in the mesangial region (Robbins)