What was Krakauer's main concern as he began his descent?

• A. His oxygen was depleting.
• B. Weather worsening.
• C. Dehydration.
• D. Frostbite.

Answer: (A)

At high altitude, oxygen is the lifeline that keeps you thinking clearly and moving steadily. As Krakauer began his descent, the oxygen supply he relied on was running out. Without enough oxygen, hypoxia takes hold, dulling judgment, slowing reactions, and sapping energy—precisely the combination that makes retreat down the mountain dangerous. That immediate risk of losing breathable air is why his main concern was the depleting oxygen.

Weather worsening, dehydration, or frostbite are serious on Everest, but none threaten his ability to descend as directly and urgently as running out of oxygen. If the oxygen runs dry, the whole descent can quickly become untenable, regardless of those other factors.