Negative pressure ventilation, demonstrated by iron lungs, allows a person to breathe by producing an intermittent negative pressure that moves across the chest and diaphragm. this specific action would artificially induce the intrapulmonary pressure to atmospheric pressure thus resulting in . drop below; inspiration. b. drop below; expiration. c. move above; inspiration. d. move aboe; expiration.

The above mentioned specific action would artificially induce the intrapulmonary pressure to drop below atmospheric pressure thus resulting in inspiration

Explanation:

The process of ventilation through negative pressure by the mechanical iron lung in respiration, provides a person with the ability to breathe if that person has the disability to breathe due to some disease.

We normally breathe by this pressure, in which the contraction of diaphragm and expansion of chest makes the pulmonary pressure to drop and enabling the air to flow inside it from atmosphere. This inward flowing of air is regarded as ‘inspiration’.

d i think its   answer d