The correct answer is: C. Total internal reflection.
Total internal reflection is the optical 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. At the critical angle, the light is refracted at an angle of 90 degrees to the normal, and no light is transmitted into the second medium.
Optical fibers work on the principle of total internal reflection. The core of an optical fiber has a higher refractive index than the cladding, which is the outer layer of the fiber. When light enters the core of the fiber, it is refracted at an angle to the normal. If the angle of incidence is greater than the critical angle, the light will be totally internally reflected at the core-cladding interface. This allows light to travel along the length of the fiber without being lost.
Scattering is the process of redirection of a beam of light by particles of a much smaller wavelength. Interference is the superposition of two or more waves to produce a resultant wave having characteristics of the two interfering waves. Refraction is the bending of light as it passes from one medium to another.
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