show as we go down the group, the Nobel character decreases.
Helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn are the Nobel gas and from group 8A.
As we go down the group, the ionization energy decreases and reactivity increases.
In general, ionization energy decreases from top to down. Because the nuclear pull over a valence electron decreases.
Hence, the option C is correct