What role do vitamins play in the body?

Vitamins play a crucial role in the body by supporting various functions that are essential for maintaining overall health. Specifically, they are vital for metabolic processes, which involve converting food into energy and facilitating numerous biochemical reactions necessary for sustaining life. Additionally, vitamins strengthen the immune system, helping the body defend against infections and diseases. They also contribute to energy production by acting as coenzymes, which assist enzymes in their function and ensure that energy is effectively released and utilized from nutrients.

The other options do not accurately reflect the comprehensive role of vitamins. For instance, while the body requires energy sources, carbohydrates and fats serve as the primary energy sources rather than vitamins. Muscle building is a function more associated with proteins and certain minerals rather than being a primary role of vitamins. Lastly, while vitamins are important for health, they do not eliminate the need for water, as hydration is critical for all bodily functions and is essential for the overall metabolic processes in conjunction with vitamins.