Afalling blood ph and a rising partial pressure of carbon dioxide usually indicate:
a. respiratory acidosis
b. respiratory alkalosis
c. metabolic acidosis
d. metabolic alkalosis.

The correct option is: a. respiratory acidosis        

Explanation:

Respiratory acidosis is a serious medical condition which is characterized by hypoventilation i.e. decrease in ventilation. Hypoventilation causes an increase in the carbon dioxide concentration in blood, thus increasing the partial pressure of carbon dioxide which leads to a decrease in the pH of the blood. Respiratory acidosis is of two types: acute and chronic.

the ileocecal valve (also called bauhin valve), which limits the rate of food passage into the cecum and may prevent material from returning to the small intestine.