Which of the following options represents the correct bond order?

According to molecular orbital theory,the total number of bonding electron pairs in $O_2$ is

Match List-$I$ with List-$II$.

List-$I$ (Molecule)	List-$II$ (Number and types of bond/s between two carbon atoms)
$A.$ Ethane	$I.$ One $\sigma$-bond and two $\pi$-bonds
$B.$ Ethene	$II.$ Two $\pi$-bonds
$C.$ Carbon molecule,$C_2$	$III.$ One $\sigma$-bond
$D.$ Ethyne	$IV.$ One $\sigma$-bond and one $\pi$-bond

Choose the correct answer from the options given below:

In the conversion of $N_2$ into $N_2^+$,the electron will be lost from which of the following molecular orbitals?

Thermal decomposition of $AgNO_3$ produces two paramagnetic gases. The total number of electrons present in the antibonding molecular orbitals of the gas that has the higher number of unpaired electrons is. . . . .

The magnetic property of $NO_2$ is