The ornamental design for a wrench, as shown and described above.
FIG. 1 is a top plan view of an ornamental design for a wrench of the present invention;
FIG. 2 is a right side plan view of an ornamental design for a wrench of the present invention;
FIG. 3 is a front plan view of an ornamental design for a wrench of the present invention;
FIG. 4 is a left side plan view of an ornamental design for a wrench of the present invention;
FIG. 5 is a rear plan view of an ornamental design for a wrench of the present invention;
FIG. 6 is a bottom plan view of an ornamental design for a wrench of the present invention;
FIG. 7 is a top isometric view of an ornamental design for a wrench of the present invention;
FIG. 8 is a second top isometric view of an ornamental design for a wrench of the present invention;
FIG. 9 is a top plan view of an alternate embodiment of an ornamental design for a wrench of the present invention as disclosed above with reference to FIG. 1, the difference being the number of holes included in the handle portion;
FIG. 10 is a bottom plan view of an alternate embodiment of an ornamental design for a wrench of the present invention as disclosed above with reference to FIG. 6, the difference being the number of holes included in the handle portion;
FIG. 11 is a top isometric view of an alternate embodiment of an ornamental design for a wrench of the present invention as disclosed above with reference to FIG. 7, the difference being the number of holes included in the handle portion; and,
FIG. 12 is a second top isometric view of an alternate embodiment of an ornamental design for a wrench of the present invention as disclosed above with reference to FIG. 8, the difference being the number of holes included in the handle portion.