Choose the correct option.
I. On an average, a healthy human breathes 12-16 times/minute.
II. The volume of air involved in the breathing movements can be estimated by a spirometer.
III. Diaphragm is very useful in both inspiration and expiration.

Which of the above statements are correct?

The correct option is D I, II and III
I. On an average, a healthy human breathes 12-16 times/minute.

II. The volume of the air involved in breathing movements can be estimated by using a spirometer, which helps in the clinical assessment of pulmonary functions.

III. The diaphragm is the most efficient muscle of breathing. It is a large, dome-shaped muscle located at the base of the lungs. Abdominal muscles help move the diaphragm and helps to empty the lungs.