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
After effective cardiopulmonary resuscitation there is: 
Select and explain. 
A. Constriction of pupil, B. Dilation of pupil, C. Elevation of BP, D. None of the above
A: Constriction of pupil
Answer: A: Constriction of pupil 
Explanation: None