The ornamental design for a ring, as shown and described.
FIG. 1 is a front view of the ring of the present invention, the back view being a mirror image;
FIG. 2 is a left side view of the ring of FIG. 1, the right side being a mirror image;
FIG. 3 is a bottom view of the ring of FIG. 2 taken along the line 3—3 in the direction of the appended arrows; and,
FIG. 4 is a top view of the ring of FIG. 1.
The broken line showing of parts of the drawings is included for the purpose of illustrating use and environment and forms no part of the claimed design.