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: Physiology
Cyanosis does not occur in severe anaemia because 
Select and explain. 
A. Hypoxia stimulates erythropoietin production, B. Oxygen carrying capacity of available haemoglobin is increased, C. Critical conc. Of Hb required to produce cyanosis is reduced, D. Oxygen haemoglobin curve shift to right
C: Critical conc. Of Hb required to produce cyanosis is reduced
Answer: C: Critical conc. Of Hb required to produce cyanosis is reduced 
Explanation: None