Which of the following is reduced by $Zn-Hg/HCl$ to give the corresponding hydrocarbon?

Phenylmagnesium bromide,upon reaction with a compound $X$ followed by treatment with acid,gives benzyl alcohol. The compound $X$ is

Two compounds $A$ and $B$ with the same molecular formula $(C_{3}H_{6}O)$ undergo Grignard's reaction with methylmagnesium bromide to give products $C$ and $D$. Products $C$ and $D$ show the following chemical tests.

Test	$C$	$D$
Ceric ammonium nitrate Test	Positive	Positive
Lucas Test	Turbidity obtained after five minutes	Turbidity obtained immediately
Iodoform Test	Positive	Negative

$C$ and $D$ respectively are:

Addition of hydrogen cyanide $(HCN)$ to carbonyl compounds is:

Write the structural formulas and names of the four possible aldol condensation products from propanal and butanal. In each case,indicate which aldehyde acts as the nucleophile and which acts as the electrophile.

Identify the method that gives benzyl alcohol.