Which of the following tests can be used to distinguish between $C_2H_5CHO$ and $(CH_3)_2CO$?

Consider the following reaction. The structure of the main product will be

$2,2-$dichloropropane $\stackrel{Aq. KOH}{\longrightarrow} A$ $\xrightarrow{\text{Clemmensen reduction}} B$. $B$ is

Toluene $\xrightarrow[(2) \ H_3O^{+}]{(1) \ CrO_2Cl_2 / CS_2} X$ $\xrightarrow{\text{Conc. } NaOH} Y + Z$. The correct statements about $Y$ and $Z$ are:
$A. \quad Y$ is a secondary alcohol
$B. \quad Y$ is the reduction product of $X$
$C. \quad Z$ on heating with soda lime gives benzene
$D. \quad Y$ does not give $H_2$ gas with $Na$ metal

Which of the following compounds has the highest boiling point?

Product $(A)$ is