Assertion (A) : ${\text{CO}}_2$ is non polar and ${\text{SO}}_2$ and ${\text{H}}_2\text{O}$ are polar.

Reason (R) : ${\text{CO}}_2$ has linear structure while ${\text{SO}}_2$and ${\text{H}}_2\text{O}$ have “V – shaped” structure.

The structure of ${\text{CO}}_2$ molecule is shown below.

 The geometry of ${\text{CO}}_2$ is a linear so that it is a non polar molecule.

Therefore, ${\text{CO}}_2$ has zero dipole moment.

The structure of ${\text{H}}_2\text{O}$ molecule is shown below.

 Water is a polar molecule so that it has dipole moment.

The structure of (${\text{SO}}_2$) molecule is shown below.

 Sulphur dioxide (${\text{SO}}_2$) is a polar molecule and therefore it has dipole moment.