Nitrobenzene on further excessive nitration gives

Assertion : Nitrobenzene is used as a solvent in Friedel-Craft's reaction.
Reason : Fusion of nitrobenzene with solid $KOH$ gives a low yield of a mixture of $o-$ and $p-$ nitrophenols.

In which of the following compounds does electrophilic attack occur at ortho and para positions?

The major product of the following reaction is:

Chlorobenzene is:

Describe the electrophilic substitution reactions of chlorobenzene.