This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Microbiology
Shift of oxygen binding curve to the left occurs because of 
Select and explain. 
A. Increased 2,3-DPG, B. Increased temperature, C. Increased PCO2, D. Stored blood
D: Stored blood
Answer: D: Stored blood 
Explanation: Causes of the shift to the left include:Decreased H+(increased pH).Decreased 2,3-DPG.Stored blood.Polycythemia Decreased temperatureDecreased P CO2Causes of the shift to the right include:Increased H+( decreased pH)Increased 2,3-DPGIncreased temperatureIncreased PCO2