During inspiration, the diaphragm
a)	Expands	b)	Shows no change
c)	Contracts and flattens	d)	Relaxes to become dome-shaped

(c)

Periodically, filling the lung with atmospheric air and then emptying, is called breathing or ventilation of lungs. Breathing in is called inspiration or inhalation and breathing out is called expiration or exhalation. During inhalation or inspiration, the diaphragm contracts putting backwards by partial flattening and increase the thoracic cavity lengthwise.