The product of the following reaction is:

Identify product $A$ in the following reaction:
$C_6H_5N_2^+Cl^- \xrightarrow{C_2H_5OH} A + N_2 + CH_3CHO + HCl$

The major product formed in the following reaction is:

Which one of the following compounds forms a quaternary salt on reacting with excess methyl iodide?

The reaction of aniline with excess liquid bromine gives $......$.

Identify the product in the following reaction sequence:
$3,4,5-\text{Tribromoaniline} \xrightarrow[\text{(ii) } H_3PO_2]{\text{(i) diazotization}} ?$