Answer the following question:
 
You are given rock salt, benzene and ice. In which of these does the light travel fastest? Use the information given in Table.
 
YCIND_220926_4499_Light reflection and Refraction_18.png
Absolute refractive index of some material media
 
The speed of light in medium is to the refractive index.
 
So, light travels faster in  as compared to others.