Two thin slabs of refractive indices `mu_(1)` and `mu_(2)` are placed parallel to each other in the x-z plane. If the direction of propagation of a ray in the two media are along the vectors `vec(r)_(1) = a hati +b hatj` and `vec(r)_(2) = c hati +d hatj` then we have:

Options

A. `mu_(1) a = mu_(2)b`
B. `(mu_(1)a)/(sqrt(a^(2)+b^(2))) = (mu_(2)a)/(sqrt(c^(2)+d^(2)))`
C. `mu_(1) (a^(2)+b^(2)) = mu_(2) (c^(2)+d^(2))`
D. None of these