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: Physiology
Hematocrit relates to which of the following: 
Select and explain. 
A. Total blood volume, B. Total RBC volume, C. Total WBC volume, D. Plasma filtrate
B: Total RBC volume
Answer: B: Total RBC volume 
Explanation: None