Answer the following question given this paragraph: 

Like the formation of ions, the formation of charged matter in general depends on the transfer of electrons either between two materials or within a material. Three ways this can occur are friction, conduction, and polarization. In all cases, the total charge remains the same. Electrons move, but they aren’t destroyed. This is the law of conservation of charge .


Q: Electrons move, but they aren’t destroyed. this is the law of conservation of what?

 Choices:

- energy

- cost

- matter

- charge

A:
charge
