This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Physiology
Most impoant from of carbon-dioxide transpo in the blood 
Select and explain. 
A. It is mostly transpoed as carboxy hemoglobin, B. As dissolved CO2, C. As bicarbonates, D. Due to CO2 molecules attached to hemoglobin
C: As bicarbonates
Answer: C: As bicarbonates 
Explanation: The route by which most of the carbon dioxide is carried in the bloodstream. Once dissolved in the blood plasma, carbon dioxide combines with water to form carbonic acid, which immediately ionizes into hydrogen and bicarbonate ions. The bicarbonate ions serve as pa of the alkaline reserve.Ref: Ganong&;s Review of Medical Physiology; 24th edition; page no: 644