The semicarbazone of cyclobutanone is represented as:

$OCH-CHO \xrightarrow{OH^{-}} HOCH_2-COO^-$. The reaction given is:

The correct statement about the synthesis of pentaerythritol $(C(CH_2OH)_4)$ used in the preparation of $PETN$ is

Give the reaction of $(a)$ acetaldehyde and $(b)$ acetone with $(i)$ $NaHSO_{3}$ and $(ii)$ $HCN$.

The intermediate $J$ in the following Wittig reaction is

Given below are two statements: One is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$ : $Image-I$ can be easily reduced using $Zn-Hg / HCl$ to $Image-II$.
Reason $R : Zn-Hg / HCl$ is used to reduce carbonyl group to $-CH_2-$ group.
In the light of the above statements,choose the correct answer from the options given below: