To determine which species has the highest bond order, we need to calculate the bond order for each species.Bond order is calculated using the formula:Bond order=2Number of bonding electrons − Number of antibonding electronsLet's analyze each species:1. CN+• Total electrons: 6(C)+7(N)−1=12• Electron configuration: (σ1s)2(σ1s∗)2(σ2s)2(σ2s∗)2(π2px)2(π2py)2(σ2pz)2• Bond order: 28−4=22. CN−• Total electrons: 6(C)+7(N)+1=14• Electron configuration: (σ1s)2(σ1s∗)2(σ2s)2(σ2s∗)2(π2px)2(π2py)2(σ2pz)2(π2px∗)2• Bond order: 210−4=33. NO• Total electrons: 7(N)+8(O)=15• Electron configuration: (σ1s)2(σ1s∗)2(σ2s)2(σ2s∗)2(π2px)2(π2py)2(σ2pz)2(π2px∗)1• Bond order: 210−5=2.54. CN• Total electrons: 6(C)+7(N)=13• Electron configuration: (σ1s)2(σ1s∗)2(σ2s)2(σ2s∗)2(π2px)2(π2py)2(σ2pz)1• Bond order: 29−4=2.5Comparing the bond orders, CN− has the highest bond order of 3.Therefore, the species with the highest bond order is CN−, which corresponds to Option 2.