Increasing the Number of Stomata Per Unit Surface Area of a Leaf

Multiple Choice

Increasing the number of stomata per unit surface area of a leaf when atmospheric carbon dioxide levels decline is most analogous to which of the following human adaptations?

A) breathing faster as atmospheric carbon dioxide levels increase
B) putting more red blood cells into circulation when atmospheric oxygen levels decline
C) removing red blood cells from circulation when atmospheric oxygen levels increase
D) increasing the volume of its lungs when atmospheric carbon dioxide levels increase