**Core Concept**
Pigmented basal cell carcinoma is a rare variant of basal cell carcinoma, characterized by the presence of melanin pigment. It is essential to differentiate it from other pigmented lesions, such as melanoma, to ensure appropriate treatment.

**Why the Correct Answer is Right**
The treatment of choice for pigmented basal cell carcinoma is Mohs surgery, also known as Mohs micrographic surgery. This technique involves the removal of the tumor in thin layers, with examination of each layer under a microscope to ensure complete removal of the tumor. Mohs surgery is particularly useful for pigmented basal cell carcinoma because it allows for the preservation of surrounding tissue and minimizes the risk of recurrence. The procedure is also highly effective, with a high cure rate.

**Why Each Wrong Option is Incorrect**
**Option A:** Excision with wide margins is not the preferred treatment for pigmented basal cell carcinoma because it may result in significant tissue loss and scarring. Additionally, it may not ensure complete removal of the tumor.
**Option B:** Radiation therapy is not typically used to treat pigmented basal cell carcinoma, as it may not be effective in eradicating the tumor completely.
**Option C:** Cryotherapy is not a suitable treatment for pigmented basal cell carcinoma, as it may not be effective in removing the tumor, and it can result in scarring and pigmentary changes.

**Clinical Pearl / High-Yield Fact**
Remember that pigmented basal cell carcinoma can mimic other pigmented lesions, such as melanoma, and therefore requires a thorough diagnostic workup to ensure accurate diagnosis and treatment.

**Correct Answer:** C.