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

A known artificial sweetener $\mathbf{X}$ is composed of 4-chloro-4-deoxy- $\alpha$-D-galactose and 1,6-dichloro-1,6-dideoxy- $\beta$-D-fructose joined by a glycosidic linkage. Structure of D-galactose is given below :

The correct structure of $\mathbf{X}$ is

Correct statement(s) about the compounds P, Q and R is(are)