It would be 7 because the acid and base cancel out each other
Answer - Inter-molecular attractions
Explanation-
As we know everything around us is made up of matter that means everything has molecules as their basic structure. The state of anything is decided by the spaces between the molecules.
The state of the objects that have strong inter-molecular attractions a solid and gradually the lesser will be in state of liquid and gas. The attraction between the molecules is overcome only when a certain amount of energy is provided from outside.
The best answer is the first option. A bike rusting is an example of a chemical change since rusting is a chemical reaction. New substances are formed from this reaction. On the other hand, other choices given are just physical changes because only the shape or the physical form of the substances are being changed.
