What is the primary function of Servo tabs in an aircraft?

Servo tabs are specifically designed to make control surfaces easier to move. When attached to control surfaces such as ailerons, elevators, or rudders, these tabs move in the opposite direction to the control surface itself. This movement creates a pressure differential that reduces the control forces required to maneuver the aircraft. By lightening the pilot's workload, servo tabs enhance the overall efficiency of the control system, allowing for smoother and more responsive handling, especially in larger aircraft where control surfaces can be heavy or cumbersome to operate.

The other options do not accurately represent the function of servo tabs. While they do not directly increase speed, reduce drag, or assist in navigation, the primary function remains focused on reducing the effort needed to operate the control surfaces.