In the following sequence of reaction $CH_3CH_2OH \quad \underrightarrow {P+I_2} \quad A \quad \underrightarrow {Mg} \quad B \quad \underrightarrow {HCHO} \quad C \quad \underrightarrow {H_2O} D$ the compound D is :

Question

$\begin{array}{1 1} Butanal \\ n-butyl\;alcohol \\ n- propylalcohol \\ propanal \end{array}$