The ornamental design for a ring, as shown and described.
FIG. 1 is a front view of a ring according to my new design;
FIG. 2 is a back view of the ring shown in FIG. 1;
FIG. 3 is a right side view of the ring shown in FIG. 1;
FIG. 4 is a left side view of the ring shown in FIG. 1;
FIG. 5 is a top view of the ring shown in FIG. 1;
FIG. 6 is a bottom view of the ring shown in FIG. 1; and,
FIG. 7 is a top frontal perspective view of the ring shown in FIG. 1.
The ornamental design which is claimed is shown in solid lines in the drawings. Any broken lines in the drawings are for illustrative purposes only and form no part of the claimed design.