Which of the following is formed when benzaldehyde reacts with concentrated sodium hydroxide?

Preparation of looking mirrors involves the use of

$R$ formed in the following sequence of reaction is:

Methyl vinyl ketone on reaction with $LiCuMe_2$ gives a major product,whose structure is

Reaction of a carbonyl compound with one of the following reagents involves nucleophilic addition followed by elimination of water. The reagent is

Acetaldehyde and acetone differ in their reaction with