Which of the following processes is not properly matched with its description?
a. external respiration: co2 diffuses into the blood stream
b. transport of respiratory gases: o2 is bound to hemoglobin
c. internal respiration: o2 diffuses out of the blood
d. pulmonary ventilation: movement of gases into and out of the lungs

External respiration: CO2 diffuses into the blood

Explanation:

External respiration is also called the pulmonary gas exchange. It refers to the diffusion of O2 from the air in the alveoli of the lungs to blood in pulmonary capillaries and diffusion of CO2 in the opposite direction from the capillary blood into the alveolar air. External respiration in the lungs is responsible for oxygenation of deoxygenated blood coming from the right side of the heart. The oxygenated blood is then returned to the left side of the heart.  

i believe the answer would be b. hope it : )