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
Most accurate for measurement of ECF volume 
Select and explain. 
A. Deuterium oxide, B. Cr-51 labeled RBC, C. Inulin, D. Albumin
C: Inulin
Answer: C: Inulin 
Explanation: ECF volume is measured using inulin which is a polysaccharide.(Ref: Textbook of physiology N Geetha 2nd edition page no.61)