What does this signal indicate?

• The red light is about to appear. You must stop if you can do so safely.
  Explanation:

  "A yellow or amber traffic light indicates that the signal is about to turn red. You should stop if you can do so safely. If stopping safely isn't possible, you should proceed through the intersection with caution."
• The green light is about to appear. You must increase your speed.
• You must come to a complete stop.
• You can turn left or right.