The reaction shown below is known as:-
$C_6H_5COCl + H_2 \xrightarrow{Pd-BaSO_4} C_6H_5CHO + HCl$
(Benzoyl chloride $\rightarrow$ Benzaldehyde)

Identify $Z$ in the following sequence of reactions.
$C_2H_4Br_2$ $\xrightarrow[\text{(ii) } NaNH_2]{\text{(i) alc- } KOH} X$ $\xrightarrow[\text{Red hot}]{\text{Fe tube, } 873 \ K} Y$ $\xrightarrow[\Delta]{\left(CH_3CO\right)_2O / \text{Anhyd-} AlCl_3} Z$

$Ph - C \equiv C - CH_3 \xrightarrow{Hg^{2+}/H^+} A$. What is $A$?

Consider the following statements. Acetophenone can be prepared by:
$1$. Oxidation of $1$-phenylethanol
$2$. Reaction of benzaldehyde with methyl magnesium bromide
$3$. Friedel-Crafts reaction of benzene with acetyl chloride
$4$. Distillation of calcium benzoate

Which sequence represents the best synthesis of hexanal?
$CH_3CH_2CH_2CH_2CH_2CH=O$ (Hexanal)

In the following sequence of reactions:
$C_6H_5CH_3$ $\xrightarrow{KMnO_4} A$ $\xrightarrow{SOCl_2} B$ $\xrightarrow{H_2/Pd, BaSO_4} C$
the product $C$ is: