**Core Concept**
Amyloidosis is a group of conditions characterized by the deposition of amyloid fibrils in various tissues, leading to organ dysfunction. Confirming the diagnosis of amyloidosis requires a definitive method to identify the presence of amyloid fibrils.

**Why the Correct Answer is Right**
The best method for confirming amyloidosis is through the use of Congo Red staining on tissue biopsy. This involves staining a tissue sample with Congo Red dye, which binds to the amyloid fibrils. Under polarized light, the stained amyloid fibrils exhibit a characteristic green birefringence, confirming the presence of amyloid deposits. This method is considered the gold standard for diagnosing amyloidosis.

**Why Each Wrong Option is Incorrect**
**Option A:** Serum protein electrophoresis (SPEP) is a useful screening test for amyloidosis, but it is not a definitive method for confirming the diagnosis.
**Option B:** Immunofixation electrophoresis (IFE) can help identify the type of amyloid protein involved, but it is not a direct method for confirming amyloid deposition.
**Option C:** Imaging studies such as CT or MRI can help identify organ involvement in amyloidosis, but they are not specific for diagnosing amyloidosis.

**Clinical Pearl / High-Yield Fact**
A key clinical finding in amyloidosis is the presence of macroglossia (enlargement of the tongue), which is due to amyloid deposition in the tongue muscles.

**Correct Answer: C. Imaging studies such as CT or MRI can help identify organ involvement in amyloidosis, but they are not specific for diagnosing amyloidosis.