Which component is affected by drag in aviation?

Drag in aviation is a force that opposes the forward motion of an aircraft through the air. It is primarily influenced by factors such as the shape of the aircraft, its speed, and the density of the air. When considering the options, the flight path of an aircraft is indeed significantly affected by drag. As drag increases, the aircraft must exert more thrust to maintain its speed or altitude, which can change its trajectory and overall performance in flight.

The flight path describes the trajectory that the aircraft takes during its operation, and any changes in speed, altitude, or direction are influenced by the balance between thrust and drag. When drag increases due to various conditions, the flight path can alter to compensate for the increased resistance, leading to adjustments in control inputs or power settings.

In contrast, the other components, such as thrust, control surfaces, and stability, may play roles in the overall performance and handling of the aircraft but are not directly defined as being affected by drag. Instead, they all interact with drag to some extent during flight operations, but the concept of drag uniquely pertains to how it directly influences the flight path. Understanding this relationship is crucial for pilots when managing an aircraft's performance.