GATEverse — GATE CSE previous year questions

Consider the following two sets:

\begin{array}{|ll|ll|}\hline & \textbf{Set X} & & \textbf{Set Y} \\\hline \text{ P.} & \text{Lexical Analyzer } & \text{1.}& \text{Abstract Syntax Tree} \\\hline \text{ Q.}& \text{Syntax Analyzer} & \text{2.} & \text{Token} \\\hline \text{ R.} & \text{Intermediate Code Generator} &\text{3.} & \text{Parse Tree} \\\hline \text{ S.} & \text{Code Optimizer} &\text{4.} & \text{Constant Folding} \\\hline \end{array}

Which one of the following options is the CORRECT match from Set $\boldsymbol{X}$ to Set $\boldsymbol{Y}$ ?