Final answer:
The sum of the expiratory reserve volume, tidal volume, and inspiratory reserve volume equals the Vital Capacity (VC).
Step-by-step explanation:
The sum of the expiratory reserve volume (ERV) plus the tidal volume (VT) plus the inspiratory reserve volume (IRV) equals the Vital Capacity (VC). These three volumes contribute to the amount of air a person can voluntarily move in and out of their lungs. Specifically, the ERV is the additional air that can be exhaled after a normal exhalation, the VT or TV is the regular volume of air that is inhaled and exhaled during normal breathing, and the IRV is the additional air that can be inhaled after a normal inhalation. The option that corresponds to the sum of these three volumes, according to the provided information, is Vital Capacity (VC), making option c) the correct answer.