What should you do when approaching a stopped school bus with its upper alternating red lights flashing?

• You must come to a complete stop.
  Explanation:

  "You must stop whenever you approach a stopped school bus with its upper alternating red lights flashing, regardless of whether you are behind the bus or approaching it from the front."
• You should slow down and slowly pass through the bus.
• You should change your lane and pass through without caution.
• You should speed up and pass through as quickly as you can.