What is 'C' in the given sequence of reactions?





In this reaction sequence, an aromatic compound undergoes a reaction with NaNO2/HCl, followed by hydrolysis with H2O/H3PO4, leading to the formation of a carboxyl group (COOH) as product 'C'.
(i) Explain Aldol condensation with example.
(ii) How are the following conversions achieved:
(a) Benzene Benzaldehyde, (b) Ethanoic acid ethanol.