In the reaction,the acid obtained will be
$CH_3CHO + HCN \to CH_3CH(OH)CN \xrightarrow{H_2O} CH_3CH(OH)COOH$

An aromatic compound $A$ (Molecular formula $C_{8}H_{8}O$) gives a positive $2,4-DNP$ test. It gives a yellow precipitate of compound $B$ on treatment with iodine and sodium hydroxide solution. Compound $A$ does not give Tollen's or Fehling's test. On drastic oxidation with potassium permanganate,it forms a carboxylic acid $C$ (Molecular formula $C_{7}H_{6}O_{2}$),which is also formed along with the yellow compound in the above reaction. Identify $A, B$ and $C$ and write all the reactions involved.

Identify the products $(A)$ and $(C)$ in the following reaction sequence:
$Cyclopentyl-^{14}CN + CH_3MgBr$ $\xrightarrow{H_3O^\oplus} (A)$ $\xrightarrow{NaOI} (B) + (C)$

Which one of the following is the major product of the given reaction?

Which of the following is most reactive towards nucleophilic addition reaction?

The structure shown in the figure is best classified as a(an):