Electrophilic aromatic substitution is difficult in

Among the following, the reaction that proceeds through an electrophilic substitution, is:

In the following reactions

$\mathrm{X}$ and $\mathrm{Y}$, respectively, are:

The major product obtained in the given reaction is:

The compounds $\mathrm{A}$ and $\mathrm{B}$ in the following reaction are, respectively:

The major product of the following reaction is: