This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General physiology, Subject name: Physiology
ECF is measured by 
Select and explain. 
A. Inulin, B. D2O, C. Evan's blue, D. 3H2O
A: Inulin
Answer: A: Inulin 
Explanation: Ref: Ganong&;s review of medical physiology; 23ed edition, page no:2 Inulin A polysaccharide with the general formula C6nH10n+2O5n+1 that yields fructose when hydrolyzed and is found in the roots of many plants, especially those of the composite family. It is used as an additive in processed foods to replace fat or sugar and to increase fiber content.