The correct answer is: B. Broadening of transmitted light pulses along the channel.
Dispersion is the broadening of transmitted light pulses along the channel. It is caused by the different wavelengths of light traveling at different speeds through the fiber. This causes the pulses to spread out over time, which can reduce the signal quality.
There are two main types of dispersion: modal dispersion and chromatic dispersion. Modal dispersion is caused by the different paths that light can take through the fiber. Chromatic dispersion is caused by the different wavelengths of light traveling at different speeds through the fiber.
Modal dispersion can be reduced by using a single-mode fiber, which has a core that is only large enough for one mode of light to propagate. Chromatic dispersion can be reduced by using a fiber with a lower refractive index difference between the core and cladding.
Dispersion is a major limitation in optical fiber communication. It can be mitigated by using a fiber with a lower refractive index difference between the core and cladding, or by using a single-mode fiber.
A. Compression of light pulses is not a correct answer because dispersion causes the pulses to spread out over time, not compress.
C. Overlapping of light pulses on compression is not a correct answer because dispersion causes the pulses to spread out over time, not overlap.
D. Absorption of light pulses is not a correct answer because dispersion does not cause light to be absorbed.