The correct answer is: Attenuation.
Attenuation is the loss of power in a signal as it travels through a medium. In the case of optical fibers, attenuation is caused by scattering and absorption of light by the fiber’s material.
Scattering is the redirection of light by particles in the fiber’s material. This can happen when light hits a particle at an angle, or when the particle is larger than the wavelength of light. Scattering can cause light to lose energy and become scattered in different directions.
Absorption is the conversion of light energy into heat energy. This can happen when light hits a particle that absorbs light of a particular wavelength. Absorption can cause light to lose energy and become absorbed by the fiber’s material.
Attenuation can be reduced by using a fiber with a lower loss material, or by using a fiber with a larger diameter. A fiber with a lower loss material will have less scattering and absorption, and a fiber with a larger diameter will have less scattering.
Attenuation is an important factor to consider when designing an optical fiber system. The amount of attenuation in a fiber will determine the maximum distance that light can travel through the fiber before it loses too much power.