Which molecule has the highest bond order

The number of species from the following which are paramagnetic and with bond order equal to one is___________

$\mathrm{H}_2, \mathrm{He}_2^{+}, \mathrm{O}_2^{+}, \mathrm{N}_2^{2-}, \mathrm{O}_2^{2-}, \mathrm{F}_2, \mathrm{Ne}_2^{+}, \mathrm{B}_2$

Which of the following molecular orbitals has maximum number of nodal planes ?

Given below are two statements:

Statement $(I)$ : A $\pi$ bonding $MO$has lower electron density above and below the inter-nuclear asix.

Statement $(II)$ : The $\pi^*$ antibonding $MO$ has a node between the nucles.In the light of the above statements, choose the most appropriate answer from the options given below:

According to molecular theory, the species among the following that does not exist is

Among the following species, the diamagnetic molecule is