Correct Answer - C
The thoracic cavity is anatomically an air tight chamber as it consists of lungs that further consists of air sacs in which the air remains trapped. The contraction of the external intercostal muscles lifts up the ribs the sternum. RBCs transport both `O_(2)` and `CO_(2)`. Healthy man can inspire or expire `6000` to `8000` mL of air pre minute.