What does a diamond-shaped marking in the center of a traffic lane typically indicate?

• The lane is only for vehicles making a right turn.
• The lane is about to end or merge with another lane.
• The lane is designated for high-occupancy vehicles (HOVs) or other special use.
  Explanation:

  "This sign indicates that the lane is reserved for high-occupancy vehicles (HOVs) such as carpools, buses, or other vehicles meeting specific requirements. Other vehicles may not use this lane during restricted hours."
• The lane is reserved for emergency vehicles only.