Aldehydes Ketones And Carboxylic Acids

Natural rubber on complete ozonolysis $\left(\mathrm{O}_3 / \mathrm{Zn}-\mathrm{H}_2 \mathrm{O}\right)$ gives compound $\mathbf{X}$ as the major product. $\mathbf{X}$ gives positive iodoform and Tollen's tests. $\mathbf{X}$ on heating with aqueous NaOH gives $\mathbf{Y}$ as the major product. $\mathbf{Y}$ is