Which of the following ions has the maximum number of unpaired d-electrons?

$\displaystyle \mathrm{Fe}^{3+}$

$\displaystyle \mathrm{V}^{3+}$

$\displaystyle \mathrm{Ti}^{3+}$

$\displaystyle \mathrm{Sc}^{3+}$ [Atomic number: $\displaystyle \mathrm{Fe}=26, \mathrm{~V}=23, \mathrm{Ti}=22, \mathrm{Sc}=21$ ]