Question id 488 - Human Performance and Limitations - ATPL - Airline Transport Pilot license

Hypoxia is the lack of sufficient oxygen to meet the needs of the body tissues which require oxygen to fight infection or invading bacteria.
Hypoxia is the lack of sufficient oxygen to meet the needs of the body tissues which require oxygen to coagulate the blood in case of infection.
Hypoxia is the lack of sufficient oxygen to meet the needs of the body tissues which require carbon dioxide for metabolism.
Hypoxia is the lack of sufficient oxygen to meet the needs of the body tissues which require oxygen for oxidation of carbohydrates from food to produce energy.