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

1. If you see the train’s lights, stop 20 meters before the crossing.
2. Correct answer: Slow down and prepare to stop before the crossing, if necessary.
3. Drive faster and cross the railway tracks.
4. Stop at a distance of 12 meters from the railway tracks to check if a train is approaching.

WhyYou are approaching a crossing: slow down and be ready to stop if needed. Numbers like 12 or 20 meters in the other answers are made up.