Chemistry · Classification of Elements and Periodicity in Properties

Which of the following elements belongs to the 3d transition series?

1. A
   Lanthanum (\( Z = 57 \))
2. B
   Yttrium (\( Z = 39 \))
3. C
   Scandium (\( Z = 21 \))
4. D
   Actinium (\( Z = 89 \))