Hypervitaminosis of which of the following will cause bony abnormalities –a) Vitamin Ab) Vitamin Dc) Vitamin Cd) Vitamin Ee) Vitamin K

**Core Concept**
Hypervitaminosis refers to the excessive intake of vitamins, which can lead to various adverse effects on the body. In this question, we are asked to identify the vitamin that causes bony abnormalities when taken in excess.

**Why the Correct Answer is Right**
Vitamin D is essential for bone health, and its excessive intake can lead to hypervitaminosis D, also known as vitamin D toxicity. This condition can cause bony abnormalities, including softening of the bones (osteomalacia) in adults and skeletal deformities in children. The excessive vitamin D can activate osteoclasts, leading to bone resorption and an imbalance in bone remodeling.

**Why Each Wrong Option is Incorrect**
**Option A:** Vitamin A is primarily associated with retinopathy, liver damage, and bone fractures due to increased bone resorption, but it is not the primary cause of bony abnormalities.
**Option B:** Vitamin E is known for its antioxidant properties and is not typically associated with bony abnormalities.
**Option C:** Vitamin C is essential for collagen synthesis and is not typically associated with bony abnormalities.
**Option D:** Vitamin K is crucial for blood clotting and is not typically associated with bony abnormalities.

**Clinical Pearl / High-Yield Fact**
Remember that excessive intake of vitamin D can lead to an imbalance in calcium and phosphorus metabolism, resulting in hypercalcemia and secondary hyperparathyroidism, which can cause bony abnormalities.

**Correct Answer: C. Vitamin D**