The question asks about the hybridization and geometry of the complex ion \([Mn(CN)_6]^{3-}\). To determine the correct hybridization and geometry, follow these steps:
Based on the above analysis, the correct statement is: "It is \(d^2sp^3\) hybridised and octahedral."
Explanation of other options:
The IUPAC name for the complex \( [\text{Co}(\text{ONO})(\text{NH}_3)_5]\text{Cl}_2 \) is