Which of the following is correct for ${N_2}$ triple bond

Which of the following species contain only  $\pi \,-\,$ bond but exhibit paramagnetic nature ?

Of the species, $NO , NO ^{+}, NO ^{2+}, NO ^{-},$ the one with minimum bond strength is :

Which of the following molecules/ions does not contain unpaired electrons?

According to Molecular Orbital Theory,

($A$) $\mathrm{C}_2^{2-}$ is expected to be diamagnetic

($B$) $\mathrm{O}_2{ }^{2+}$ is expected to have a longer bond length than $\mathrm{O}_2$

($C$) $\mathrm{N}_2^{+}$and $\mathrm{N}_2^{-}$have the same bond order

($D$) $\mathrm{He}_2^{+}$has the same energy as two isolated He atoms

The pair of species that has the same bond order in the following is