Transition metals are hard and lustrous substances with high melting points and form highly coloured compounds. Which of the following is not transition metals?

The correct option is D Aluminium, lead and tin

Transition metals are defined as those elements which have partially filled d sub-shell, or which can give rise to cations with an incomplete d-subshell. Transition metals constitute the d-block of the periodic table, which includes groups 3 to 12 on the periodic table.

There are 3 transition series namely 3d series, 4d series and 5d series respectively. First transition series or 3d series starts from scandium and ends with zinc includes iron, chromium, and nickel. In the above elements, Aluminium is of group 13 while lead and tin are of group 14 elements, hence, they are not transition metals.