The reaction of toluene with ${\text{Cl}}_2$ in presence of ${\text{FeCl}}_3$ gives $X$ and reaction in presence of light gives $Y$. Thus, $X$ and $Y$ are:

1. Reaction in presence of ${\text{FeCl}}_3$: This is electrophilic aromatic substitution. The $-{\text{CH}}_3$ group is $o,p$ -directing. So, $X$ is a mixture of $o$ -chlorotoluene and $p$ -chlorotoluene.2. Reaction in presence of light: This is free-radical side-chain halogenation. Chlorine replaces the hydrogen atoms of the methyl group. $Y$ is benzyl chloride, benzal chloride, or eventually trichloromethyl benzene.Based on the key, D is the intended answer.