Answer: D
BrFX2X+: Br has 7−1=6 valence electrons, 2 used in bonds, leaving 2 lone pairs. So 4 pairs, sp3, bent. BrFX4X−: 7+1=8 electrons, 4 used in bonds, leaving 2 lone pairs. So 6 pairs, sp3d2, square planar. The anion is thus isostructural with XeFX4.