High-Velocity Stars Are Isolated Stars That Swing in and Out

High-velocity stars are isolated stars that swing in and out of the plane of the galaxy at relatively high velocities with respect to the solar system. Where would you expect to find them?

A) moving rapidly toward the solar system from all directions because of cosmic explosions in the open clusters where they are produced
B) in the rotating disk of the galaxy, having relatively large velocities with respect to the solar system because of their positions in the disk
C) in orbit around the galactic halo
D) circling the entire galaxy, just outside the galactic plane