**Core Concept**
Parathyroid adenoma is a benign tumor of one of the parathyroid glands, leading to primary hyperparathyroidism characterized by excessive parathyroid hormone (PTH) production. This results in hypercalcemia, a condition where calcium levels in the blood are elevated.

**Why the Correct Answer is Right**
The primary goal of treatment for parathyroid adenoma is to normalize calcium levels, alleviate symptoms, and prevent long-term complications. Surgery, specifically parathyroidectomy, is the preferred treatment for parathyroid adenoma. This involves removing the affected parathyroid gland to restore normal PTH production. The surgical approach can be either open or minimally invasive, and the choice depends on the surgeon's expertise and the patient's condition.

**Why Each Wrong Option is Incorrect**
**Option A:** Medical management with bisphosphonates is not the primary treatment for parathyroid adenoma. While bisphosphonates can help manage hypercalcemia, they do not address the underlying cause of the condition.
**Option B:** Vitamin D supplementation is not the primary treatment for parathyroid adenoma. Vitamin D can help manage secondary hyperparathyroidism, but it does not address the underlying cause of primary hyperparathyroidism caused by parathyroid adenoma.
**Option C:** Conservative management with hydration and monitoring is not sufficient for parathyroid adenoma. While hydration and monitoring are essential for managing hypercalcemia, they do not address the underlying cause of the condition and may not be sufficient to prevent long-term complications.

**Clinical Pearl / High-Yield Fact**
Parathyroid adenoma is often asymptomatic, and diagnosis is made incidentally during evaluation for hypercalcemia or other symptoms. Regular monitoring of calcium levels and PTH production is essential to prevent complications and ensure timely treatment.

**Correct Answer:** C.