What is the factor that affects how easily an electron can be removed from an atom?

A. surrounding atoms.

B. temperature of the environment.

C. size of the atom.

D. structure of the atom

I think the correct answer among the choices listed above is option D. It is the structure of the atom that is the factor that affects how easily an electron can be removed from an atom. This is because having a stronger structure would mean that electrons have a strong attraction to the atom and it would be harder to remove the electrons.