When bar-headed geese fly at very high altitudes (possibly over Mount Everest!), they breathe very thin air where the partial pressure of oxygen is very low compared to that at sea level. Which of the following adaptions would help the geese efficiently exchange gases when flying at high altitudes? ______
A) hemoglobin that has a high affinity for oxygen
B) hemoglobin that has a high affinity for carbon dioxide
C) hemoglobin that has a low affinity for carbon dioxide
D) hemoglobin that has a low affinity for oxygen