The ornamental design for a “sink,” as shown and described.
FIG. 1 is a perspective view of a sink.
FIG. 2 is a top plan view of the sink of FIG. 1.
FIG. 3 is a bottom plan view of the sink of FIG. 1.
FIG. 4 is a front view of the sink of FIG. 1.
FIG. 5 is a rear view of the sink of FIG. 1.
FIG. 6 is a right side view of the sink of FIG. 1; and,
FIG. 7 is a left side view of the sink of FIG. 1.
The features shown in broken lines form no part of the claimed design. FIGS. 1-7 include solid lines, but it is the Applicant's intention to disclose all of the features of FIGS. 1-7 as part of the specification and to reserve the right to claim any or all of those features in any combination in this or a continuing application by converting any one or more solid lines of FIGS. 1-7 into broken lines in order to claim any aspect(s) of this disclosed design in isolation or in any combination. The Applicant's disclosure is, thus, not limited to the initial claim reflected in FIGS. 17 but encompasses every aspect of FIGS. 1-7 alone and/or in combination.