To maintain safety in flight, what should pilots monitor with respect to hypoxia?

Monitoring oxygen levels is vital for pilots to maintain safety in flight, particularly to prevent hypoxia, which is a deficiency in the amount of oxygen reaching the tissues. As altitude increases, the amount of available oxygen decreases, making it essential for pilots to be aware of their oxygen supply. This awareness helps ensure that they can provide sufficient oxygen to themselves and their passengers, especially in situations where cabin pressure may fail or at higher altitudes where breathable air is less available.

While factors like weather patterns, altitude, and air traffic routines are important for overall flight safety, they do not directly address the specific physiological concerns related to hypoxia. Understanding and managing oxygen levels allows pilots to make informed decisions to maintain alertness and performance during flight. Hence, monitoring oxygen levels is the most pertinent aspect when it comes to preventing hypoxia, making it the correct choice in this context.