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: Pathology
Flow cytometry is done to know ? 
Select and explain. 
A. Rapid cell shrinkage, B. Blood flow to brain, C. Net O2 supply to tissues, D. Amount of O2 bound to hemoglobin
A: Rapid cell shrinkage
Answer: A: Rapid cell shrinkage 
Explanation: Ans. is 'a' i.e., Rapid cell shrinkage