Final answer:
The total cross-sectional area of the airways increases as the airways divide into smaller branches, similar to the branches of a tree in relation to its trunk.
Step-by-step explanation:
The correct answer to the question "Total cross-sectional area ________ with each division of the airways" is A) increases. As the airways branch out and divide into smaller passages, the number of airways increases, and if you were to add up the cross-sectional area of these numerous smaller airways, this total area is greater than that of the larger airways they originated from. This is similar to how the roots and branches of a tree divide and spread out, creating more surface area than the single trunk they diverge from.