A patient with a normal dead-space-to-tidal-volume ratio (VD/VT) of 30% is breathing 12 times per minute with a tidal volume of 500 mL. The patient then suffers a pulmonary embolism with the resultant increase of VD/VT to 50%. To maintain constant alveolar ventilation, the patient will
A. Decrease tidal volume to 340 mL
B. Increase respiratory frequency to 16 breaths per minute
C. Decrease respiratory frequency to 8 breaths per minute
D. Maintain current tidal volume
E. Maintain current respiratory frequency