The correct option is D Partly dissolved in plasma and partly in the form of sodium and potassium bicarbonate
Blood transports carbon dioxide in three ways, namely: (1) as carbonic acid (2) as bicarbonates of sodium and potassium (3) as carbaminohaemoglobin. About 10% of total carbon dioxide is carried by the blood in the dissolved state as carbonic acid; 80% of CO2 as sodium bicarbonate and potassium bicarbonate in the plasma and as potassium bicarbonate in the corpuscles and the remaining 10% as carbamino-haemoglobin.