Which of the following is a function of vitamin C?

Vitamin C, also known as ascorbic acid, plays several vital roles in the body, one of the most notable being its promotion of collagen synthesis. Collagen is an essential structural protein that is a key component of connective tissues such as skin, cartilage, tendons, ligaments, and blood vessels. Vitamin C is required for the hydroxylation of proline and lysine residues in collagen, a critical step that stabilizes its structure. This function of vitamin C is crucial for maintaining skin integrity, wound healing, and overall structural support within the body.

The other options do not accurately reflect the known functions of vitamin C. For example, calcium absorption is primarily facilitated by vitamin D, while phosphorus levels in the body are not significantly influenced by vitamin C. Similarly, energy storage in the liver primarily pertains to glycogen, which involves carbohydrates rather than vitamin C. Understanding the specific roles of vitamins is essential for grasping their importance in nutrition and health.