Which among the following is NOT dicarboxylic acid?

Identify the product ' B ' in the following sequence of reactions.

$$ \text { Methylpropanoate } \xrightarrow[\text { dil. } \mathrm{NaOH}]{\Delta} \mathrm{A} \xrightarrow[\text { Conc. } \mathrm{HCl}]{\mathrm{H}^{+}} \mathrm{B} $$

Cyclohexene on oxidation with $\mathrm{KMnO}_4$ in dil. $\mathrm{H}_2 \mathrm{SO}_4$ forms

Identify the product formed in the following reaction.