Identify the position where $E.A.S.$ (Electrophilic Aromatic Substitution) will take place.

When benzene is treated with excess of $Cl_2$ in the presence of $FeCl_3$ (or $I_2$ as a carrier),the end product is:

The product $(A)$ is:

Benzene on treatment with a mixture of conc. $HNO_3$ and conc. $H_2SO_4$ at $100 \ ^oC$ gives

Given below are two statements:
Statement $I$: Nitration of benzene involves the following step:
$H-O^+(H)-NO_2 \rightleftharpoons H_2O + NO_2^+$
Statement $II$: Use of Lewis base promotes the electrophilic substitution of benzene.
In the light of the above statements,choose the most appropriate answer from the options given below:

Which of the following statements are correct?
$I$. In nitrating mixture,nitric acid participates as an acid.
$II$. $\sigma$-complex is the intermediate substance in electrophilic substitution of benzene.
$III$. Benzene on Friedel-Crafts alkylation with $n$-propyl chloride gives isopropyl benzene.