Why is it not the safest choice to pass a school bus that has flashing amber lights?

• It indicates that the bus is reducing speed.
• The bus may be stopping.
• Both A and B.
  Explanation:

  "It is not the safest choice to pass a school bus that has flashing amber lights, indicating that it is reducing speed, because it may be stopping to allow passengers on and off the school bus. If you do proceed, do it with caution."
• None of the above.