Answer:
The correct option is: E. 70 square meters
Step-by-step explanation:
Pulmonary alveoli is described as the cup-shaped hollow cavity, found in the alveolar sacs of mammalian lungs.
The alveolar membrane, also called the respiratory membrane, allows the exchange of gases. Across this membrane, carbon dioxide is released from the capillaries into the alveoli and oxygen is diffused from the alveoli into the capillaries.
About 300 million alveoli are present in the lungs of a human, which makes about 70m² of surface area.