What is hypoxia?

Hypoxia is defined as an oxygen deficiency that is significant enough to impair normal physiological functions. This condition can occur at various altitudes, particularly in aviation, where the availability of oxygen decreases as altitude increases. When there is inadequate oxygen delivered to the tissues, a variety of symptoms can manifest, including confusion, decreased coordination, and, in severe cases, loss of consciousness.

Understanding hypoxia is crucial for pilots and individuals operating at high altitudes because recognizing its signs can be vital for maintaining health and ensuring operational safety.

The other options do not accurately depict hypoxia. An increase in oxygen availability, for example, denotes hyperoxia and not hypoxia. A condition characterized by excess carbon dioxide correlates with hypercapnia, while an increase in blood pressure is entirely unrelated to oxygen levels and instead relates to cardiovascular dynamics. These distinctions highlight why the chosen answer is specifically correct in the context of aerospace physiology.