This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Physiology
During exercise, blood flow to brain is 
Select and explain. 
A. Decreased, B. Increased, C. Unaltered, D. Initially increased and then decreases
C: Unaltered
Answer: C: Unaltered 
Explanation: There is no change in the cerebral blood flow