An organic compound (A) (molecular formula $\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_2$ ) was hydrolysed with dil. $\mathrm{H}_2 \mathrm{SO}_4$ to give a carboxylic acid (B) and an alcohol (C). 'C' gives white turbidity immediately when treated with anhydrous $\mathrm{ZnCl}_2$ and conc. HCl . The organic compound $(A)$ is