Final answer:
The correct answer is b) Decreased respiratory rate. Tidal volume refers to the amount of air inhaled or exhaled during a normal breath. A decrease in tidal volume means that less air is being moved in and out of the lungs with each breath.
Step-by-step explanation:
The correct answer is b) Decreased respiratory rate. Tidal volume refers to the amount of air inhaled or exhaled during a normal breath. A decrease in tidal volume means that less air is being moved in and out of the lungs with each breath. One of the factors that can cause a reduction in tidal volume is a decreased respiratory rate, as the lungs are taking in less air overall. For example, during sleep or in certain medical conditions like respiratory failure, the body may decrease the respiratory rate to conserve energy, resulting in a decrease in tidal volume.