JEE Advanced Model Paper 4 with solutions for online practice

As the ray moves toward the normal while entering medium 2 from 1, we have
n2 > n1
for total internal reflection at interface of 2 and 3, n2 > n3
Besides n3 should also be less than n1 or else ray would have emerged mmedium 3, parallel to its path in medium 1. Hence n3 < n1 < n2 is the correct order