The metal ion whose electronic configuration is not affected by the nature of the ligand and which gives a violet colour in non-luminous flame under hot condition in borax bead test is:
\( \mathrm{Ni}^{2+} \)
\( \mathrm{Ti}^{3+} \)
\( \mathrm{Cr}^{3+} \)
\( \mathrm{Mn}^{2+} \)
