**Core Concept**
Wegener's granulomatosis, also known as granulomatosis with polyangiitis (GPA), is a form of vasculitis that affects small- and medium-sized vessels. It is characterized by the presence of granulomas and necrotizing vasculitis, which can lead to damage in various organs including the kidneys.

**Why the Correct Answer is Right**
The characteristic feature of Wegener's glomerulonephritis is the presence of crescentic glomerulonephritis. This is due to the deposition of immune complexes and activation of complement, leading to inflammation and damage to the glomeruli. The crescents are formed by the proliferation of parietal epithelial cells and the migration of monocytes/macrophages into Bowman's space. This process is mediated by the release of various cytokines and chemokines, including TNF-alpha, IL-1, and IL-6.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because while IgG and IgM deposits can be seen in various forms of glomerulonephritis, they are not the characteristic feature of Wegener's glomerulonephritis.
**Option B:** This option is incorrect because fibrinoid necrosis is a feature of polyarteritis nodosa, not Wegener's granulomatosis.
**Option C:** This option is incorrect because the presence of neutrophils is a feature of various forms of glomerulonephritis, but it is not the characteristic feature of Wegener's glomerulonephritis.

**Clinical Pearl / High-Yield Fact**
Wegener's granulomatosis is a classic example of a small-vessel vasculitis that can affect multiple organs, including the kidneys, lungs, and skin. The presence of crescentic glomerulonephritis is a hallmark of this condition and can be a key diagnostic clue.

**Correct Answer:** C.