Among the following cyclic ions,which exhibit aromatic character?

The product $(B)$ in the above reaction is:

$n-hexane$ $\xrightarrow{\text{catalyst}}$ benzene
The catalyst is:

Cyclic hydrocarbon molecule $A$ has all the carbon and hydrogen atoms in a single plane. All the carbon-carbon bonds are of the same length and are less than $1.54 \ \mathring{A}$ but more than $1.34 \ \mathring{A}$. The $C-C-C$ bond angle will be:

$2 \text{ Benzene} \xrightarrow[{AlCl_3}]{{CH_2Cl_2}} \text{ Product}$

Consider the following reactions:
$C_2 H_2 \xrightarrow[500^{\circ}C]{\text{red hot iron tube}} A$
$A \xrightarrow[70^{\circ}C]{\text{conc. } HNO_3, \text{conc. } H_2 SO_4} B$
$B \xrightarrow{LiAlH_4} C_6 H_5-N=N-C_6 H_5$
$A$ and $B$ are: