Which combination of conditions may result in the maximum torque effect in a single-engine aircraft?

The combination of high power, low airspeed, and a steep bank generates the maximum torque effect in a single-engine aircraft due to the physics of flight dynamics. When an aircraft is producing high power, the engine provides a significant amount of thrust, which in turn increases the torque. Torque is the rotational force that the propeller exerts, and its tendency to roll the aircraft in the opposite direction is more pronounced at low airspeed because the aircraft's wings produce less lift, making it less stable and more susceptible to roll.

A steep bank angle further exacerbates this effect because it increases the load factor on the aircraft. In a steep bank, the lift vector is tilted, which requires more engine thrust to maintain altitude. This additional thrust increases torque and makes the roll tendency more pronounced. Therefore, under these circumstances, the aircraft faces a greater risk of rolling in the direction opposite to the propeller's rotation due to the higher torque effect.

In contrast, the other combinations of conditions would not create the same level of torque effect. Low power, high airspeed, and a shallow bank would typically result in a more stable flight condition where the effects of torque are minimized.