What do the white arrows in the center lane indicate?

• The white arrows indicate that vehicles can use this lane for through driving and passing.
• The white arrows indicate that vehicles must turn right from this lane.
• The white arrows indicate that vehicles can use this lane to turn left, and should use it with caution as vehicles from the opposite direction may also be using it to turn left.
  Explanation:

  "The white arrows in the center lane indicate that this lane is designated as a two-way left-turn lane. This means vehicles traveling in either direction can use this lane to make left turns."
• The white arrows indicate that vehicles must stop in this lane.