question_answer

The respiratory system (involving inhalation and exhalation processes) is responsible for taking in oxygen rich air and expelling carbon dioxide rich air. Which of the following is the sequence in which events occur in the inhalation process? P: Air pressure inside your lungs drops. Q: The diaphragm contracts. R: Air from outside rushes into your lungs.

A)  P, Q, R            

B)  Q, P, R

C)       R, P, Q

D)       Q, R, P