What was wrong with the climbers who were above Peak's group?

• A. There were two cases of HAPE at Camp 6 and one mild case at Camp 5, and two climbers had left after midnight to go to the summit and hadn't been seen since.
• B. They were simply exhausted from the altitude.
• C. They had run out of oxygen.
• D. They were delayed by weather.

Answer: (B)

At high altitude, the body has less oxygen to work with, so physical effort costs more energy and fatigue sets in quickly. If there aren’t clear signs of a medical altitude illness (like trouble breathing at rest, confusion, or loss of coordination) and there’s no indication of equipment failure or weather-related delays, the most plausible explanation for climbers above Peak’s group is simply exhaustion from the altitude. In other words, their energy and endurance were overwhelmed by the thin air, rather than a specific emergency.