Among the following series of transition metals ions,the one where all metal ions have $3d^2$ electronic configuration is

Question

$\begin{array}{1 1}(a)\;Ti^{3+},V^{2+},Cr^{3+},Mn^{4+}\\(b)\;Ti^{+},V^{4+},Cr^{6+},Mn^{7+}\\(c)\;Ti^{4+},V^{3+},Cr^{2+},Mn^{3+}\\(d)\;Ti^{2+},V^{3+},Cr^{4+},Mn^{5+}\end{array}$