What does broncho constriction during an asthmatic attack reflect?

A decrease in the diameter of the conducting zone airways

B is correct A is wrong because the respiratory zone has no smooth muscle C is wrong because bronchoconstriction deals with smooth muscle not with alveolar sacs. D is wrong because reistance in the airways actually INCREASES with bronchoconstriction E is wrong because the diffusion of respiratory gases occurs in the respiratory zone at the alveoli. Bronchoconstriction does not occur at this location