Where are ailerons located on an aircraft?

Ailerons are crucial components of an aircraft's control surfaces, and they are specifically located on the outboard trailing edges of the wings. Their primary function is to control the roll of the aircraft, allowing it to tilt to the left or right during flight. This movement is essential for maneuvers such as turning. The placement of ailerons at the trailing edge ensures they can effectively create differential lift, as one aileron moves downward to increase lift on one wing while the other moves upward to decrease lift on the opposite wing. This design contributes to effective roll control, making option B the correct choice.

Other locations such as the leading edge do not accommodate ailerons due to aerodynamic and functional design considerations, which is why those answers are less appropriate.