CLINICAL MEDICINE

Detailed explanation-1: -Quiet expiration is a passive process occurring at rest, whereas forced expiration is an active process that occurs during exercise. Quiet respiration depends on elastic recoil of the lungs after inspiratory stretching, elastic recoil of the costal cartilages, and the relaxation of the inspiratory muscles.

Detailed explanation-2: -(d) inspitation and expiration are passive processes.

Detailed explanation-3: -Inspiration occurs via active contraction of muscles – such as the diaphragm – whereas expiration tends to be passive, unless it is forced.