Explanation

(a) Optical rotation or optical activity is the rotation of linearly polarized light as it travels through certain materials. It occurs in solutions of chiral molecules ($eg$, sugar), solids with rotated crystal planes (eg, quartz) and spin polarized gases of atoms or molecules. Any linear polarization of light can be written as an equal combination of right hand (RHC) and left hand (LHC) circularly polarized light.
$E_{\theta_{D}} = E_{RHC} + e^{i2\theta D}\ E_{LHC}$
Where E is the electric field of light.