What is the phenomenon called where different wavelengths of light travel at different speeds？（）

A. amplifier
B. attenuator
C. regenerator
D. light emitter
E. optical switch
F. optical receiver
G. fiber-optic cable

A. OSNR
B. dispersion
C. attenuation
D. power budget
E. amplifier spacing
F. four wave mixing

A. PIN photodiodes
B. zero-chirped lasers
C. Erbium-doped fiber amplifiers
D. dispersion compensating fiber
E. dispersion compensating Bragg grating