Which tool is specifically designed for turning hex head socket screws?

The tool specifically designed for turning hex head socket screws is the Allen wrench, also known as a hex key. This tool has a hexagonal cross-section that perfectly fits into the recess of hex socket screws, allowing for efficient torque and grip, which is essential for tightening or loosening these types of screws.

Unlike other tools, such as a flathead screwdriver or Phillips screwdriver, which are designed for different screw types, the Allen wrench is tailored specifically to match the shape and dimensions of hex socket screws. While a Torx wrench fits a different type of screw with a star-shaped socket, it does not serve the same purpose as an Allen wrench for hex screws. Therefore, the Allen wrench is the correct choice for this particular application.