Final answer:
The drier the air outside a leaf, the faster water will be lost from the leaf through the stomata.
Step-by-step explanation:
The statement that the drier the air outside a leaf, the faster water will be lost from the leaf through the stomata is TRUE.
Leaves are covered by a waxy cuticle on the outer surface that prevents the loss of water. Regulation of transpiration is achieved primarily through the opening and closing of stomata on the leaf surface. When stomata are open, water vapor is lost to the external environment, increasing the rate of transpiration. Therefore, in drier air, with lower humidity, the stomata open wider, resulting in a faster water loss from the leaf.