At what altitude does Extreme Hypoxia occur?

• A. 15,000 ft
• B. 20,000 ft
• C. 25,000 ft
• D. 30,000 ft

Answer: (B)

As you ascend, the air becomes thinner, so each breath supplies less oxygen. The brain is very sensitive to oxygen shortage, and while the body can compensate for a while, there’s a limit. When oxygen delivery to the brain falls below what it needs, hypoxia progresses from mild to more severe stages, and at extreme levels the brain can’t function properly and consciousness can be lost very quickly. That rapid, severe impairment defines extreme hypoxia. Among the given options, the altitude associated with reaching that extreme level is the highest one, because only at that higher height does the oxygen shortfall become severe enough to cause such rapid deterioration. The lower options would still involve hypoxia, but not to the point of immediate, severe impairment.