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: Pathology
The best method for estimation of hemoglobin concentration in blood: 
Select and explain. 
A. Acid hematin method, B. Alkali hematin method, C. Cyanmethemoglobin method, D. Any of the above
C: Cyanmethemoglobin method
Answer: C: Cyanmethemoglobin method 
Explanation: None