Which of the following is a key function of the Reshape tool?

The Reshape tool is primarily designed to modify existing geometry of features within a layer. This tool allows users to alter the shape of polygons, polylines, or other geometric entities by adding, removing, or adjusting vertices. This functionality is particularly valuable for refining and editing spatial data to accurately reflect real-world scenarios or to meet specific project requirements.

In contrast, changing the coordinates of a layer does not fully capture the primary role of the Reshape tool; rather, it implies altering the position without necessarily modifying the shape. Converting raster to vector is an entirely different process that involves changing data formats rather than altering existing geometries. Creating new mapping styles focuses on the presentation and visualization of spatial information, which is outside the scope of geometry modification. Thus, the Reshape tool specifically excels in enhancing the existing geometrical form of features within a GIS context.