What does a properly designed airfoil achieve during flight?

A properly designed airfoil is primarily focused on generating lift and reducing drag, which are two critical factors for efficient flight. Lift is the upward force that counteracts the weight of the aircraft, allowing it to rise off the ground and stay airborne. The shape and angle of the airfoil are designed to create a pressure differential above and below the wing, which results in the generation of lift.

Reducing drag is equally important, as lower drag means the aircraft can maintain speed with less engine power, leading to greater fuel efficiency and improved performance. A well-designed airfoil minimizes the resistance encountered as the aircraft moves through the air, which directly contributes to better overall flight performance.

While other options touch on related concepts, they either do not capture the essential roles of lift and drag in relation to airfoil design or contain components that may not be entirely relevant to the primary purpose of an airfoil in flight. Therefore, the answer that highlights the dual capability of generating lift while simultaneously reducing drag best reflects the fundamental objectives achieved by a well-designed airfoil.