On what ground can you say that scandium `(Z=21)` is a transition element but zinc `(Z=30)` is not?

Explanation

E.C of `""_(21)Sc=1s^(2)2s^(2)2p^(6)3s^(2)3p^(2)3d^(1)4s^(2)`. In this E.C 3d orbital have one electron in its ground state . That is why it is regarded as a transition element.
E.C of Zn=`1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(10)4s^(2)`
Zn does not have partly filled orbital in its ground state or in its excited state that is why it is not considered as a typical transition element .