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
C02 is primarily transpoed in the aerial blood as: 
Select and explain. 
A. Dissolved C02, B. Carbonic Acid, C. Carbamino-hemoglobin, D. Bicarbonate
D: Bicarbonate
Answer: D: Bicarbonate 
Explanation: Transpo of carbon dioxide in the form of bicarbonate ions accounts for approximately 70% of the carbon dioxide transpoed from the tissues to the lungs. Thus this is by far the most impoant of all methods of transpo. Ref: Textbook of Medical Physiology By Guyton, 10th Edition, Page 471