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
Edema is visible when the amount of fluid accumulated is: March 2013 (d, f) 
Select and explain. 
A. 2-3 litres, B. 3-4 litres, C. 4-5 litres, D. 5-6 litres
D: 5-6 litres
Answer: D: 5-6 litres 
Explanation: Ans. D i.e. 5-6 litres