JEE Main 2025 Jan 29 Shift 1, Chemistry Q9: Preparation of Alkyl Halides (Halo Alkanes) & Aryl Halides (Halo Arenes)

The substrate undergoes nucleophilic aromatic substitution ($S_{N}Ar$) via the addition-elimination (Meisenheimer) pathway. Ethoxide attacks a ring carbon bearing $\mathrm{Br}$, and the intermediate carbanion is stabilised only if the negative charge can be delocalised onto the $\mathrm{N}{\mathrm{O}}_2$ group at ortho or para to the leaving Br.

Of the two C-Br positions, only the one para to $-\mathrm{N}{\mathrm{O}}_2$ has this stabilisation, so that Br is displaced. The remaining Br (ortho to $\mathrm{N}{\mathrm{O}}_2$ in the original numbering, now ortho to the new $\mathrm{O}{\mathrm{C}}_2{\mathrm{H}}_5$) stays intact.

Hence product P is 2-bromo-1-ethoxy-4-nitrobenzene, i.e. option (1).