Define level crossing:

1. A place where a road and a railroad meet on a freeway.
2. A place where a road and a railroad meet at different levels.
3. Correct answer: A place where a road and a railroad meet or cross at the same level.
4. Any place where a railroad can be crossed

WhyA level crossing is where a road crosses rails at the same level, marked with a special sign. If the road goes over or under the tracks, it is not a level crossing.