The cyanide ion $(CN^{-})$ and $N_2$ are isoelectronic. However,in contrast to $CN^{-}$,the $N_2$ molecule is chemically inert due to:

Statement $I$: Dipole moment is a vector quantity and by convention it is depicted by a small arrow with tail on the positive centre and head pointing towards the negative centre.
Statement $II$: The crossed arrow of the dipole moment symbolizes the direction of the shift of charges in the molecules.
In the light of the above statements,choose the most appropriate answer from the options given below :-

$CO$ is practically non-polar since

If the dipole moment of chlorobenzene is $\mu$,what is the dipole moment of $1,3,5$-trichlorobenzene?

Which one of the following compounds has a non-zero dipole moment?

Which compound exhibits the maximum dipole moment among the following?