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). ‘$\mathrm{C}$ ’ gives white turbidity immediately when treated with anhydrous ${\mathrm{ZnCl}}_2$ and conc. $\mathrm{HCl}$. The organic compound (A) is: