Which of the following describes a direct result of modifying airfoil shape?

Modifying the shape of an airfoil typically enhances its aerodynamic properties. One of the most significant effects is the ability to generate increased lift at higher angles of attack. When you alter the airfoil shape, you can optimize the pressure distribution over the wing, allowing it to maintain performance even when the angle of attack increases.

In particular, a well-designed airfoil can delay flow separation, which is crucial for maintaining lift. When the angle of attack rises, flow separation can occur, leading to stall, but a modified shape can push the stall point to a higher angle, allowing the wing to produce more lift before losing its aerodynamic efficiency. This is fundamental in aircraft design, especially for those requiring good performance in varying flight conditions.

In terms of the other options, they either imply a negative consequence of airfoil modification or do not directly relate to the primary purpose of airfoil design, which is to enhance performance and efficiency through better lift characteristics. Thus, the modification that leads to increased lift at higher angles of attack is a crucial benefit sought in aerodynamics.