**Core Concept**
Parathyroid adenoma is a benign tumor of the parathyroid gland, leading to primary hyperparathyroidism, characterized by excessive secretion of parathyroid hormone (PTH), resulting in hypercalcemia.

**Why the Correct Answer is Right**
The treatment of choice for parathyroid adenoma is surgical resection of the adenoma. This approach aims to remove the source of excessive PTH production, thereby normalizing calcium levels and alleviating symptoms. The surgery typically involves a minimally invasive approach, such as a parathyroidectomy, which is often performed through a small incision in the neck. This method allows for precise removal of the adenoma while preserving the remaining parathyroid tissue.

**Why Each Wrong Option is Incorrect**
**Option A:** Medical management, such as bisphosphonates and calcimimetics, may be used to control symptoms and calcium levels in the short term but is not a definitive treatment for parathyroid adenoma.
**Option B:** Vitamin D and calcium supplements may be prescribed to manage hypocalcemia that can occur post-surgery but are not a primary treatment for parathyroid adenoma.
**Option C:** Radiotherapy is not a standard treatment for parathyroid adenoma and is not effective in reducing PTH secretion.

**Clinical Pearl / High-Yield Fact**
It's essential to differentiate between primary and secondary hyperparathyroidism, as the treatment approach differs. Primary hyperparathyroidism is caused by an underlying parathyroid gland disorder, whereas secondary hyperparathyroidism is a response to low calcium levels, often seen in chronic kidney disease.

**Correct Answer: C. Radiotherapy is not a standard treatment for parathyroid adenoma and is not effective in reducing PTH secretion.**