Final answer:
The correct answer is D. Tidal volume, which is the amount of air inhaled or exhaled during a normal resting breath, typically around 500 milliliters in adults.
Step-by-step explanation:
The normal resting breath is also referred to as the tidal volume (TV). A direct answer to the student's question is:
The explanation is as follows: Tidal volume is the amount of air that normally enters the lungs during quiet breathing, approximately 500 milliliters for the average adult. This is in contrast to the other respiratory volumes, such as inspiratory reserve volume (IRV), expiratory reserve volume (ERV), and residual volume (RV). IRV is the extra air inhaled during a deep breath, beyond the tidal volume, while ERV is the additional air exhaled forcefully after a normal exhalation. RV is the air left in the lungs after a maximal exhalation and is key in preventing alveolar collapse. Respiratory capacity, on the other hand, is a term that refers to the combination of two or more individual volumes.
Tidal volume is the amount of air that enters the lungs during normal breathing. It is approximately 500 milliliters for an average adult. Tidal volume represents the volume of air exchanged with each breath during quiet breathing.