Dispersion-shifted single mode fibers are created by __________

Optoelectronics and Optical Communication 

Dispersion-shifted single mode fibers are created by __________ 

a) Increasing fiber core diameter and decreasing fractional index difference 
b) Decreasing fiber core diameter and decreasing fractional index difference 
c) Decreasing fiber core diameter and increasing fractional index difference 
d) Increasing fiber core diameter and increasing fractional index difference

Answer : - Decreasing fiber core diameter and increasing fractional index difference

It is possible to modify the dispersion characteristics of single mode fibers by tailoring of some fiber parameters. These fiber parameters include core diameter and relative index difference