The ornamental design for a bra, as shown and described.
FIG. 1 is a front perspective view of a bra showing my new design in an in-use configuration;
FIG. 2 is a front view thereof;
FIG. 3 is a right side view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a rear perspective view thereof; and,
FIG. 6 is an opposite side rear perspective view thereof.
The broken line immediately adjacent to the shaded area defines the bounds of the claimed design and forms no part thereof. The unshaded regions, including the two central regions between the shaded areas, form no part of the claimed design. The broken lines depicting the remainder of the bra show features that form no part of the claimed design.