What are you required to do according to the following road sign?

1. Use the brakes only.
2. Correct answer: Slow down and shift to low gear. Refrain from prolonged brake use.
3. Drive faster in the ascent by shifting to high gear.
4. Drive faster and shift to high gear.

WhyOn a steep descent, slow down and shift to a low gear so the engine brakes. Holding the brake for long overheats it and weakens it.