An aldehyde or ketone containing at least one $\alpha-H$ atom reacts with dilute $NaOH$ to form a $\beta-$hydroxy aldehyde or $\beta-$hydroxy ketone. This reaction is known as $—$

An optically active alkyl bromide $C_4H_9Br$ reacts with ethanolic $KOH$ to form major compound $[A]$, which reacts with bromine to give compound $[B]$. Compound $[B]$ reacts with ethanolic $KOH$ and sodamide to give compound $[C]$. One molecule of water adds to compound $[C]$ on warming with mercuric sulphate and dilute sulphuric acid at $333 \text{ K}$ to form compound $[D]$. The functional group in compound $[D]$ will be confirmed by:

The major product of the following reaction sequence is:

Product $(C)$ is

Which of the following statements is true regarding the Cannizzaro reaction?

The enolate ion that reacts with $3-$buten$-2-$one to form $(Y)$ is