Some xerophytic plants have leaves with stomata sunken in pits that contain tiny hairs, as shown in the cross-section diagram.
Why does this adaptation help the plant to survive in dry environments?
It increases the rate of carbon dioxide absorption.
It traps a layer of moist air, reducing the rate of transpiration.
It increases the surface area of the leaf for light absorption.
It enables the leaf to absorb water vapor directly from the surrounding air.