**Core Concept:** IgA Nephropathy is a chronic kidney disease characterized by the deposition of immunoglobulin A (IgA) in the glomeruli, causing inflammation and damage to the kidneys.

**Why the Correct Answer is Right:** IgA Nephropathy is primarily caused by the deposition of IgA immune complexes in the glomeruli, which leads to inflammation and damage. The deposition occurs in the mesangium, a connective tissue layer surrounding the glomerulus, which is a small blood vessel in the kidneys. This results in the clinical presentation of proteinuria (excess protein in urine), hematuria (blood in urine), hypertension, and decreased kidney function.

**Why Each Wrong Option is Incorrect:**

A. **Deposits in the tubules**: The correct answer mentions glomeruli, not tubules. Deposits in the glomeruli, not tubules, lead to the clinical manifestations of IgA Nephropathy.

B. **Deposits in the arteries**: Deposits in the glomeruli, not arteries, cause the disease process in IgA Nephropathy. Arteries are involved in other conditions like arteriosclerosis and hypertension.

C. **Deposits in the interstitium**: While inflammation and damage may occur in the interstitium (the space between nephrons), the primary site of deposition is the glomerulus, not the interstitium.

D. **Deposits in the tubules**: Similar to option A, the correct answer focuses on glomeruli, not tubules. Deposits in the glomeruli cause the clinical manifestations of IgA Nephropathy. Tubules are involved in other conditions like interstitial nephritis and nephrotic syndrome.

**Clinical Pearl:** IgA Nephropathy is the most common primary glomerulonephritis in adults worldwide, affecting both children and adults. It is named after the location of the immunoglobulin deposition, IgA (Immunoglobulin A).

**Correct Answer:** C. Deposits in the glomeruli

In summary, the correct answer is option C, which states that the deposits are found in the glomeruli. IgA Nephropathy is caused by the deposition of IgA immune complexes in the glomeruli, leading to inflammation and damage in the kidneys. This results in the clinical manifestations of the disease. The other options are incorrect because they refer to different areas of the kidney, not the primary site of deposition in IgA Nephropathy.