An Energy Level Scheme for the Orbitals of Second Row $\sigma$

An energy level scheme for the orbitals of second row diatomic molecules O₂ through Ne_2, lists the molecular orbitals in the following order of increasing energy $\sigma$ _2s < $\sigma$ *_2s < $\sigma$ _2p(z) < $\pi$ _2p(y) , $\pi$ _2p(x) < $\pi$ *_2p(y) , $\pi$ *_2p(x) < $\sigma$ *_2p(z)
Based on this energy level scheme, which statement is true about the bonds in the species, O₂, O₂⁺, O₂, O₂²?

A) O₂^- has the highest bond order.
B) O₂^2- has the highest bond order.
C) O₂ has the highest bond order.
D) O₂⁺ has the highest bond order.
E) The bond order in all these species is the same.