Which option correctly pairs the term with its definition?

Which option correctly pairs the term with its definition?

• A. Tidal Breathing — normal resting breathing
• B. Tidal Volume (VT) — volume of air remaining in the lungs after a normal expiration
• C. Functional Residual Capacity (FRC) — amount of air inhaled or exhaled with each breath under resting conditions
• D. SpO2 — total lung capacity

Answer: (B)

Understanding these terms comes from knowing what each one actually refers to in respiratory physiology. Tidal breathing is the normal, quiet breathing you do at rest, so it correctly pairs with the description “normal resting breathing.” Tidal volume, by contrast, is the amount of air moved in or out with each quiet breath, not the volume remaining in the lungs after a normal expiration; that later quantity is Functional Residual Capacity. Functional Residual Capacity is the amount of air left in the lungs after a normal exhale, not the amount inhaled or exhaled per breath. SpO2 is the oxygen saturation level in the blood, not a measure of lung capacity. So the only pairing that matches a term with its correct definition is tidal breathing with normal resting breathing.

Understanding these terms comes from knowing what each one actually refers to in respiratory physiology. Tidal breathing is the normal, quiet breathing you do at rest, so it correctly pairs with the description “normal resting breathing.” Tidal volume, by contrast, is the amount of air moved in or out with each quiet breath, not the volume remaining in the lungs after a normal expiration; that later quantity is Functional Residual Capacity. Functional Residual Capacity is the amount of air left in the lungs after a normal exhale, not the amount inhaled or exhaled per breath. SpO2 is the oxygen saturation level in the blood, not a measure of lung capacity. So the only pairing that matches a term with its correct definition is tidal breathing with normal resting breathing.