**Core Concept**
Hypervitaminosis D refers to an excessive intake or accumulation of vitamin D in the body, leading to potential toxicity. This condition can cause a range of symptoms and complications due to the hypercalcemia (elevated calcium levels) that results from excessive vitamin D.

**Why the Correct Answer is Right**
Hypervitaminosis D causes hypercalcemia, which can lead to various clinical manifestations, including kidney stone formation, nephrocalcinosis, and metastatic calcification. The elevated calcium levels can also cause neuromuscular excitability, resulting in symptoms such as muscle weakness, fatigue, and cardiac arrhythmias. Furthermore, excessive vitamin D can lead to an increased risk of cardiovascular events and mortality.

**Why Each Wrong Option is Incorrect**
**Option A:** Nausea and vomiting are common symptoms of hypervitaminosis D due to the hypercalcemia-induced gastrointestinal disturbances. This option is incorrect because it is actually a potential consequence of hypervitaminosis D.

**Option B:** Renal impairment is a well-documented complication of hypervitaminosis D, resulting from the hypercalcemia-induced nephrotoxicity. This option is incorrect because it is a known consequence of excessive vitamin D.

**Option C:** Weight loss is not a typical symptom of hypervitaminosis D. Instead, patients often experience weight gain due to increased appetite and fluid retention. This option is incorrect because it does not accurately reflect the clinical presentation of hypervitaminosis D.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that hypervitaminosis D can cause a range of symptoms, including those related to hypercalcemia, and can lead to serious complications such as kidney stone formation and renal impairment.

**Correct Answer:** C. Weight loss.