Which of the following is true regarding the stalling speed of an aircraft?

The stalling speed of an aircraft is indeed affected by the load factor, making the choice that indicates it increases in proportion to the load factor correct. When an aircraft is subjected to a load factor greater than one, such as during a turn, the effective weight increases. This increased load factor results in a higher angle of attack being required to produce enough lift to counteract the additional weight, which consequently raises the stalling speed.

In simpler terms, under normal conditions, the stalling speed is the minimum speed at which the aircraft can maintain level flight. However, when maneuvering—like banking—the aircraft experiences higher loads, requiring the wings to generate more lift, thus increasing the speed at which the aircraft will stall.

In contrast, the other choices highlight misconceptions. Changes in altitude alone do not directly influence the stalling speed in a significant way. Conditions such as weight and bank angle do impact it, as stalling speed will increase with weight and is influenced by loading conditions during turns. The notion that stalling speed remains constant regardless of weight overlooks the basic physics of lift and stall mechanics. Lastly, stalling speed does not decrease with increased bank angle; it actually increases due to the higher load factors present in a banked turn.