Clamp

FIG. 1 is a perspective view of a clamp showing my new and ornamental design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a side elevation view thereof;

FIG. 5 is an opposite side elevation view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The portions of the clamp shown in broken lines in the figures attached hereto form no part of the claimed design.