Arrange the following compounds in order of increasing dipole moment .
Toluene `(I)` m-dichlorobenzene `(II)`
o-dichlorobenzene `(III)` . P-dichlorobenzene `(IV)` .
A. `I lt IV lt II lt III`
B. `Iv lt I lt II lt III`
C. `I lt IV lt II lt III`
D. `IV lt II lt I lt III`
