Answer:
C rusting iron
Explanation:
water evaporating and melting is an example of physical change it doesn't change the H2O composition of the atoms, rubbing water on paper doesn't change any atoms or molecules. so the only answer that leaves is rusting iron because when an iron nail comes into contact with water and is then exposed to the air, it rusts, forming a brown-red substance. This process changes the chemical composition of the original substance.
