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
Below …………………………. pressure, CSF absorption stops - 
Select and explain. 
A. 60 mm CSF, B. 68 mm CSF, C. 80 mm CSF, D. 50 mm CSF
B: 68 mm CSF
Answer: B: 68 mm CSF 
Explanation: Below a pressure of approximately 68 mmH2O, absorption stops.