Which of the following is NOT a function of water-soluble vitamins?

Water-soluble vitamins, such as the B-complex vitamins and vitamin C, play several important roles in the body, including supporting metabolic processes, acting as antioxidants, and contributing to the health of the nervous system. However, one of their key characteristics is that they do not serve as a means of energy storage.

Unlike fat-soluble vitamins, which can be stored in the body's fatty tissues and liver, water-soluble vitamins are not stored to any significant extent. They circulate in the bloodstream and are excreted through urine if in excess. This transient nature means they must be consumed regularly through diet to maintain adequate levels.

The role of water-soluble vitamins includes facilitating energy production through metabolic processes, where they act as coenzymes in various biochemical reactions. Additionally, several of these vitamins have antioxidant properties, helping to mitigate oxidative stress in cells. They also support the nervous system's health by contributing to neurotransmitter synthesis and nerve function.

In summary, the correct answer emphasizes that water-soluble vitamins do not function to store energy in the body, distinguishing their role from other nutrients that are involved in energy storage.