Question: Which one of the following has an optical isomer ?
$\left[\mathrm{Zn}(\mathrm{en})_{2}\right]^{2+}$
$\left[\mathrm{Zn}(\mathrm{en})\left(\mathrm{NH}_{3}\right)_{2}\right]^{2+}$
$\left[\mathrm{Co}(\mathrm{en})_{3}\right]^{3+}$
$\left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)_{4}(\mathrm{en})\right]^{3+}(\mathrm{en}=$ ethylenediamine)
Correct Option: , 3
Solution:
Solution not required
