2. When oxygen moves from the alveolar gas, through the thin side of the alveolar-capillary membrane, to hemoglobin, it crosses the following layer...

2. When oxygen moves from the alveolar gas, through the thin side of the alveolar-capillary membrane, to hemoglobin, it crosses the following layers, in this order:

a) Epithelium, surfactant, interstitium, endothelium, plasma, and erythrocyte membrane.
b) Surfactant, epithelium, interstitium, endothelium, plasma, and erythrocyte membrane.
c) Surfactant, endothelium, interstitium, epithelium, plasma, and erythrocyte membrane.
d) Epithelium, interstitium, endothelium, plasma, and erythrocyte membrane.
e) Surfactant, epithelium, interstitium, endothelium, and erythrocyte membrane.