Which two aspects are considered challenging when performing the AGSM?

The choice highlighting coordination and timing as challenging aspects of performing the Anti-G (G Straining Maneuver, AGSM) is accurate because these two factors are crucial for effectively managing G-forces during high-performance maneuvers.

Coordination is vital as the AGSM requires the pilot to synchronize various body movements and breathing techniques to maintain blood flow to the brain, thus preventing G-induced Loss Of Consciousness (GLOC). This involves a precise combination of muscle contractions and relaxed posture, which can be difficult, especially under the physiological stress of high G forces.

Timing is equally important because the AGSM must be executed at the right moment during an aircraft's maneuvers to ensure maximum effectiveness. Performing the maneuver too early or too late can compromise its ability to combat G-forces and protect against blackouts.

Other choices, while relevant to certain aspects of physical performance, do not directly relate to the specific challenges posed by the AGSM during high-G flight conditions. Understanding and mastering the intricate coordination and timing required for the AGSM is essential for student pilots as they are trained to handle the physiological demands of flight.