Properties of Elements

[Electroflame1395]

Which properties of elements display a periodic variation?
A) number of electrons in outer shell
B) density
C) melting temperature
D) electronegativity
E) atomic radius
F) first ionisation energy

I thought that it would be a, d, e and f but not really sure

THANKS

[ggxoxo]

Yes, you're right; it's a, d, e, f!!!