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: Surgery
Pitting edema indicates an excess of .... litres of fluid in tissue spaces - 
Select and explain. 
A. 2.5, B. 3.5, C. 4.5, D. 5.5
C: 4.5
Answer: C: 4.5 
Explanation: None