Question

Match the items of Column I with items in Column II concerning inhalation.

Column I	Column II
A. Diaphragm	1. Increases in volume
B. Air Pressure	2. Contract
C. Intercostal muscles	3. Becomes flat
D. Thoracic cavity	4. Decreases

• A. A- 4, B- 3, C- 2, D- 1
• B. A- 3, B- 1, C- 2, D- 4
• C. A- 3, B- 4, C- 2, D- 1
• D. A- 3, B- 4, C- 1, D- 2

Answer 1

The correct option is C A- 3, B- 4, C- 2, D- 1

During inhalation, the diaphragm contracts and moves downward becoming flat. Intercostal muscles present between the ribs also contract and space in the thoracic cavity increases. Due to the increased space, the air pressure in the thoracic cavity decreases, and the air is rushed into the lungs.

Thus, the correct answer is option C.