What are you required to do when you notice the following traffic sign (in the picture) placed above your driving lane?

1. Slow down before the level crossing, and if a train is approaching - stop.
2. Correct answer: Do not enter this lane and do not continue driving in it.
3. Slow down before the level crossing and pass the tracks without delay or interruption.
4. Stop before the tracks until the train passes.

WhyA red cross over a lane means you may not drive in it: do not enter it, and if you are already in it, change lanes. It has nothing to do with railway crossings.