The third one.……...................
I believe the answer should be mates...(2)
The three methods of carbon dioxide transport in the blood are dissolution in blood plasma, binding to hemoglobin, and carried in the form of bicarbonate. About 7% of the carbon dioxide is dissolved in the blood plasma. The majority of the remaining 93% is carried as part of the bicarbonate buffer system while the rest binds to hemoglobin.