The ornamental design for an adaptablebra, as shown and described.
FIG. 1 is a front perspective view of the adaptable bra showing my new design.
FIG. 2 is a front elevation view thereof.
FIG. 3 is a rear elevation view thereof.
FIG. 4 is a bottom plan view thereof.
FIG. 5 is a left side elevation view thereof; and,
FIG. 6 is a front perspective view of the adaptable bra as worn.
The broken lines found outlining the bra straps, bra cups and the bra fasteners along with the incremented segmented lines along the interior wings of the bra, as well as the partial human figure illustrate environmental subject matter and form no part of the claimed design.