The ornamental design for a bra, as shown and described.
FIG. 1 is a front, right and top perspective view of a bra showing my new design;
FIG. 2 is a right, rear and top perspective view thereof;
FIG. 3 is a left, rear and bottom perspective view thereof;
FIG. 4 is a front view thereof;
FIG. 5 is a rear view thereof;
FIG. 6 is a left side view thereof;
FIG. 7 is a right side view thereof; and,
FIG. 8 is rear view thereof shown in an environment of use.
The broken line showing of the arms, torso and neck in FIG. 8 is for the purpose of illustrating portions of the environmental structure and forms no part of the claimed design.