Which condition can lead to a loss of control in a stall situation?

Using ailerons excessively during a stall situation can indeed lead to a loss of control. In a stall, the aircraft's wings are unable to produce sufficient lift due to an excessive angle of attack. If the pilot tries to control the aircraft by applying excessive aileron input to roll or yaw, it can exacerbate the stall condition. This is because ailerons create differential lift, which can increase the angle of attack on one wing while decreasing it on the other. If one wing reaches its critical angle of attack before the other, it can lead to a more pronounced stall on that wing, ultimately resulting in loss of control.

In contrast, the other options—like equal distribution of lift, maintaining constant airspeed, or extending flaps correctly—do not inherently lead to loss of control in a stall situation. Properly distributing lift, maintaining a steady airspeed (up to the stall speed), and configuring flaps as intended are generally factors that contribute to safe flight operations.