are solid at room temperature. are good electrical conductors. generally have very high densities. tend to form ions by gaining electrons.
I gave my students this multiple choice question: Elements on the right side of the periodic table differ from the elements on the left side in that the elements on the right side

Only one answer is correct among these 4 choices:
- are solid at room temperature.
- are good electrical conductors.
- generally have very high densities.
- tend to form ions by gaining electrons.

Could you tell me which one is correct?

tend to form ions by gaining electrons.