The hybridization and magnetic behaviour of cobalt ion in \( [\mathrm{Co}(\mathrm{NH}_3)_6]^{3+} \) complex, respectively is:
\( \mathrm{sp}^3\mathrm{d}^2 \) and paramagnetic
\( \mathrm{sp}^3\mathrm{d}^2 \) and diamagnetic
\( \mathrm{d}^2\mathrm{sp}^3 \) and diamagnetic
\( \mathrm{d}^2\mathrm{sp}^3 \) and paramagnetic