I think it’s B. I’m not 100% sure but I believe it is B! Srry if this is late btw.
Answer:
a pencil being sharpened
freezing water
boiling water
Explanation:
a physical change doesn't change the chemical structure of an object. That is why the other 2 are wrong
Answer:
No they form nitrogen oxide which can be poisonous to some species but depending on the amount of nitrogen it can be harmful to everything living. Such as if you put it with a plant that had low nitrogen levels then there would be no carbon dioxide to filter.
Explanation: