**Core Concept**
Lupus nephritis is a common complication of systemic lupus erythematosus (SLE), characterized by inflammation of the renal glomeruli, tubules, and interstitium. Wire loop lesions are a specific histopathological feature of lupus nephritis, representing thickened capillary walls due to immune complex deposition.

**Why the Correct Answer is Right**
Wire loop lesions are characteristic of class III lupus nephritis, also known as focal lupus nephritis. This class of lupus nephritis is characterized by the presence of immune complexes and complement deposits within the glomeruli, leading to thickening of the capillary walls and the characteristic wire loop appearance under light microscopy. The immune complexes and complement deposits activate the coagulation cascade, resulting in the deposition of fibrin and the formation of wire loop lesions.

**Why Each Wrong Option is Incorrect**
**Option A:** Class I lupus nephritis is characterized by minimal mesangial lupus nephritis, and wire loop lesions are not a typical feature of this class.
**Option B:** Class IV lupus nephritis is characterized by diffuse lupus nephritis, where wire loop lesions are also present, but Class III is more specifically associated with focal disease.
**Option C:** Class V lupus nephritis is characterized by membranous lupus nephritis, where the characteristic feature is the thickening of the glomerular basement membrane, not wire loop lesions.

**Clinical Pearl / High-Yield Fact**
Wire loop lesions are a hallmark of lupus nephritis and can be seen in both Class III and Class IV lupus nephritis. It's essential to distinguish between these two classes, as they have different prognoses and treatment strategies.

**Correct Answer: C. Class III lupus nephritis.**