In the presence of which of the following is the Clemmensen reduction of ketones carried out?

Give the conversion of the following:
$(i)$ $but-2-enal$ from $ethanal$
$(ii)$ $Methyl$ $benzoate$ from $benzaldehyde$

The final product $(C)$ in the given reaction sequence is
$C_6H_5COOH$ $\xrightarrow{SOCl_2} (A)$ $\xrightarrow[\text{anhy. } AlCl_3]{C_6H_6} (B)$ $\xrightarrow[\text{(ii) } KOH / (CH_2OH)_2]{\text{(i) } NH_2-NH_2} (C)$

Identify the product $Y$ in the following reaction sequence:
$CH_3CHO + CH_3MgI$ $\xrightarrow{\quad} X$ $\xrightarrow{H_2O/H^+} Y$

The conversion of acetophenone into benzoic acid can be achieved by its reaction with

Identify an aldehyde used in margarine and in food for its buttery odour.