Assertion: Nitration of benzene with nitric acid requires the use of concentrated sulphuric acid.

Reason: The mixture of concentrated sulphuric acid and concentrated nitric acid produces the electrophile, ${\mathrm{NO}}_{2}^{+}$.

1.  Both assertion and reason are true and the reason is the correct explanation of assertion.

2.  Both assertion and reason are true and the reason is not the correct explanation of assertion.

3.  Assertion is true but the reason is false.

4.  Assertion is false but the reason is true.

Hint: Nitration mixture contains conc. H2SO4 and conc. HNO3
In the nitration of benzene with nitric acid, sulphuric acid acts as a catalyst. It helps in the formation of electrophile i.e., nitronium ion ${\mathrm{NO}}_{2}^{+}$.
The reaction is as follows:
${\mathrm{HNO}}_{3}+{\mathrm{H}}_{2}{\mathrm{SO}}_{4}\to {\mathrm{NO}}_{2}^{+}+2{\mathrm{HSO}}_{4}^{-}+{\mathrm{H}}_{3}{\mathrm{O}}^{+}$