Which of the following options represents a machining operation performed on a lathe?

Boring is indeed a machining operation that is performed on a lathe. In this process, a cutting tool is used to remove material from the interior of a workpiece to create a hole or to enlarge an existing hole. The lathe allows for precise control over the cutting process, enabling adjustments to the depth and diameter of the bore.

This operation is particularly suited for cylindrical shapes, which are often created on a lathe. When compared to the other processes listed, boring stands out as a fundamental machining operation that harnesses the rotating capability of the lathe.

Welding, forging, and grinding, while significant manufacturing processes, do not typically involve a lathe. Welding joins materials using heat, forging shapes materials through mechanical force, and grinding smooths surfaces with abrasive wheels—none of these methods utilize the lathe's rotating workpiece capability for material removal like boring does. Thus, boring is the correct representation of a machining operation performed on a lathe.