the track is waxed the like poles repel the train has a low density a chemical change occurs
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Scientists have created trains that use magnets to make the trains float above the tracks as they travel. These trains float because
Possibilities:
- the track is waxed
- the like poles repel
- the train has a low density
- a chemical change occurs

the like poles repel