Item PT025001: Earth's plates move along with the slightly softened rock material below them.

Which of the following is TRUE about the movement of earth’s plates?

  1. They do not move because they sit on a layer of solid rock.
  2. They move along with the layer of slightly softened rock below them.
  3. They move by floating on a layer of completely melted rock below them.
  4. They do not move until the solid rock layer beneath them temporarily melts and moves.