**Core Concept**
Melanoma is a type of skin cancer characterized by the uncontrolled proliferation of melanocytes. The prognosis of melanoma varies depending on the thickness of the tumor, presence of lymph node metastasis, and other prognostic factors.

**Why the Correct Answer is Right**
Uveal melanoma is a type of melanoma that arises from the pigment cells of the eye, specifically from the uveal tract which includes the iris, ciliary body, and choroid. It has a worse prognosis compared to cutaneous melanoma due to its location and potential for early metastasis to the liver. Uveal melanoma often presents with advanced disease at diagnosis, making it more challenging to treat. The lack of lymphatic vessels in the eye means that the primary route of metastasis is through the bloodstream, leading to liver metastasis.

**Why Each Wrong Option is Incorrect**
**Option A:** Cutaneous melanoma has a better prognosis than uveal melanoma, especially when detected early. The thickness of the primary tumor and presence of lymph node metastasis are key prognostic factors.
**Option B:** Mucosal melanoma, including oral and genital melanoma, has a worse prognosis than cutaneous melanoma but is generally better than uveal melanoma. It often presents with advanced disease and has a higher risk of lymph node metastasis.
**Option C:** Acral melanoma, which arises from the palms, soles, or nail beds, has a worse prognosis than cutaneous melanoma but is generally better than uveal melanoma. It often presents with advanced disease and has a higher risk of lymph node metastasis.

**Clinical Pearl / High-Yield Fact**
Uveal melanoma is the most common primary malignant tumor of the eye, and early detection is crucial for improving prognosis. Patients with uveal melanoma often present with vision loss, floaters, or eye pain.

**Correct Answer:** C. Mucosal melanoma, including oral and genital melanoma, has a worse prognosis than cutaneous melanoma but is generally better than uveal melanoma.