Which measure can help reduce the risk of hypoxia during flight?

Using supplemental oxygen systems is indeed a key measure to help reduce the risk of hypoxia during flight. At higher altitudes, the partial pressure of oxygen in the atmosphere decreases, leading to lesser availability of oxygen for respiration. This can result in hypoxia, a condition characterized by insufficient oxygen reaching the tissues.

Supplemental oxygen systems provide a direct source of oxygen, ensuring that pilots and passengers receive adequate oxygen levels, even in low-pressure environments. This is particularly important during high-altitude flights, where atmospheric conditions can rapidly diminish oxygen levels. Maintaining adequate oxygen supply is crucial for sustaining cognitive functions, physical performance, and overall safety during the flight.

Other options do not effectively address the risk of hypoxia. Reducing flight altitude can help, but it's not always feasible and does not guarantee sufficient oxygen levels at higher altitudes. Increasing cabin temperature is not related to oxygen availability and can even exacerbate the sensation of fatigue, which may impair performance. Avoiding exercise before flight is not directly linked to preventing hypoxia and may not contribute to the most critical measures needed to ensure adequate oxygenation during flight.