This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
Hyperventilation results in all of the following EXCEPT 
Select and explain. 
A. increased PCO2, B. decreased cerebral blood flow, C. hypocapnia, D. increased PO2
A: increased PCO2
Answer: A: increased PCO2 
Explanation: Hyperventilation is initiated due to an increase in PCO2. The increased rate of breathing "blows off" excess CO2. Thus, hyperventilation results in a decrease of PCO2 to its normal physiologic range. The increased respiratory rate causes a ↑PO2.
The resultant decrease in CO2 causes hypocapnia.
The resultant decrease in PCO2 causes vasoconstriction, leading to ↓cerebral blood flow.
Respiratory alkalosis occurs due to the ↑pH.