Why `Zn, Cd` and `Hg` are not considered as typical transitions elements ?

Why is 'Zn' not considered as transition element ?

Why Zn, Cd and Hg are considered as soft metals?

Zn, Cd and Hg are sometimes not considered as transition elements. Give reasons with electronic configuration.

How would you account for the following? Zn, Cd and Hg are normally not considered as transition metals.

Zn, Cd, Hg are sometimes not considered as transition elements. Comment.

Assertion : Zn, Cd and Hg are not considered as transition metals. Reason :d-orbitals in Zn, Cd and Hg are completely filled, both in ground state and in their available oxidation states.

Why is copper considered to be a transition element ?