What does this traffic sign indicate?

• It indicates that bicycles are prohibited from using this roadway.
• It indicates that vehicles must maintain a minimum distance of 3 feet when passing bicycles.
  Explanation:

  "Vehicles must maintain a minimum distance of 3 feet when passing bicycles."
• It indicates that drivers must keep a 3-foot distance when stopping behind a vehicle.
• It indicates that vehicles must yield to bicycles at all times