1-Chloro-4-methylbenzene is treated with $\mathrm{NaNH}{}_2$ in liquid $\mathrm{NH}{}_3$. The number of different aromatic amine products (constitutional isomers) formed is

Loss of $\mathrm{H}$ from C-2 (ortho to $\mathrm{Cl}$) and $\mathrm{Cl}{}^{-}$ gives a benzyne with the triple bond between C-1 and C-2 ($\mathrm{CH}{}_3$ at C-4). $\mathrm{NH}{}_2{}^{-}$ adds to C-1 to give 4-methylaniline (para), or to C-2 to give 3-methylaniline (meta). The other ortho position gives the same pair, so there are 2 products.