Which of the following describes the pharyngeal stage of deglutition?
a. The stage which involves movements of the soft palate, vocal cords and larynx to temporarily close the respiratory passageways.
b. The stage where the food is involuntarily moved through the pharynx into the esophagus.
c. The stage where direct impulses to the respiratory center in the medulla decrease respiration
d. all of these answers are correct