Which of the following best defines metabolism in the context of nutrition?

The mechanical breakdown of food in the mouth and stomach without involvement of cellular chemical processes, specifically describing mastication and peristalsis as the exclusive sources of nutritional energy.

The set of chemical reactions in cells that break down and use food molecules to release energy measured in calories.

A group of voluntary behaviors such as exercise and eating patterns that determine overall energy balance but excludes biochemical reactions inside cells.

The process by which the body stores dietary energy as large inert molecules without subsequent breakdown for immediate energy use, thereby describing only anabolic reactions and excluding catabolism.