The correct answer is: C. Total internal reflection.
Fibre optics work on the principle of total internal reflection. This is the phenomenon that occurs when light passes from a medium with a higher refractive index to a medium with a lower refractive index, and the angle of incidence is greater than the critical angle. In this case, all of the light is reflected back into the first medium.
This principle is used in fibre optic cables to transmit light over long distances. The light is guided down the cable by the total internal reflection at the interface between the core and cladding of the fibre. The core is made of a material with a higher refractive index than the cladding, so the light is always reflected back into the core.
Scattering of light is the phenomenon that occurs when light is scattered in all directions by particles in a medium. This can happen when light passes through a medium with particles that are much smaller than the wavelength of light. The particles can be dust, water droplets, or even air molecules.
Total internal absorption is the phenomenon that occurs when light is absorbed by a material. This can happen when light passes through a material with a high absorption coefficient. The absorption coefficient is a measure of how much light is absorbed by the material per unit distance.
Optical rotation is the phenomenon that occurs when light is rotated as it passes through a material. This can happen when the material has a chiral structure. A chiral structure is a structure that is not identical to its mirror image.
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