Final answer:
The correct answer is A) 8,850 m - 33%, 4,500 m - 100%, showing the oxygen percentage relative to sea level. The decrease in partial pressure of oxygen at high altitudes like 8,850 meters results in lower oxygen availability, and hence climbers carry supplemental oxygen.
Step-by-step explanation:
The elevation and the percentage of oxygen available at each elevation mentioned in the question directly align with physiological changes occurring at high altitudes. At an elevation of 8,850 meters, which is roughly the summit of Mount Everest, the percentage of available oxygen is significantly reduced compared to sea level. Therefore, the correct identification of the available oxygen at specified elevations is:
A) 8,850 m - 33%, 4,500 m - 100%. The available oxygen is not 57% at 8,850 meters, but rather about 33%. Conversely, at 4,500 meters, the oxygen level is closer to the percentage found at sea level, assumed 100% for the purpose of calculations. However, it's important to note that while we say 100%, the actual percentage of inhaled oxygen utilized by the body is only about 40%, with the rest being exhaled.