When plastic deformation of a material occurs, the material regains its original shape when the stress is removed is permanently deformed becomes magnetic at low temperatures becomes highly resistant to stress

Is permanently deformed.

Explanation (see the diagram shown below).
For most structural materials:
(a) The deformation in the elastic zone is recoverable, and the material returns
      to its original shape when the load (or stress) is removed.
(b) A permanent set (non-recoverable deformation) occurs when the material
     is sressed beyond the elastic zone, that is, in the plastic zone.