Final answer:
The bulk of most people's need for energy comes from basal metabolism. The correct answer is c).
Step-by-step explanation:
The bulk of most people's need for energy is c. basal metabolism.
Basal metabolism refers to the amount of daily energy expended by humans at rest, in a neutrally temperate environment, while in the postabsorptive state. About 70% of all daily energy expenditure comes from the basic functions of the organs in the body. It is the energy required to maintain essential bodily functions such as breathing, circulating blood, regulating body temperature, and cell production.
Physical activity (option b) also contributes to the overall energy expenditure, but it usually accounts for a smaller portion compared to basal metabolism.