Answer:
D. Food
Step-by-step explanation:
During aerobic cellular respiration, animals break down organic molecules, such as glucose, to release energy that is stored in the bonds of these molecules. The energy released from the breakdown of these organic molecules is used by cells to produce ATP, which is the primary energy currency of cells.
Animals obtain the organic molecules they use in aerobic cellular respiration by consuming food, which contains these molecules in the form of carbohydrates, fats, and proteins. The organic molecules are broken down during digestion, absorbed into the bloodstream, and transported to cells throughout the body. Within cells, the organic molecules undergo a series of metabolic reactions that ultimately result in the release of energy used to produce ATP through aerobic cellular respiration.