Answer the following question given this paragraph: 

The process in which an atom becomes an ion is called ionization. It may occur when atoms are exposed to high levels of radiation or when atoms transfer electrons to or from other atoms.


Q: What process can occur when atoms are exposed to high levels of radiation or when atoms transfer electrons to or from other atoms?

 Choices:

- fusion

- diffusion

- oxidation

- ionization

A:
ionization
