Which of the following is a function performed by the digestive system?

The diagram illustrates the major regulatory mechanisms of ventilation. What mechanism does “B” represent?
a. Hering-Breuer reflex
b. receptors for touch, temperature, pain stimuli
c. medullary chemoreceptors
d. carotid and aortic body chemoreceptors
e. proprioceptors

Which of the following is a function performed by the digestive system?
a. cellular respiration
b. food selection
c. elimination of undigested food
d. regulation of blood pH
e. integration and coordination of other systems