As the beam enters the medium, it will
An initially parallel cylindrical beam travels in a medium of refractive index μ(I) = μ0 + μ2I, where μ0 and μ2 are positive constants and I is the intensity of the light beam. The intensity of the beam is decreasing with increasing radius.
(a) travel as a cylindrical beam
(b) diverge
(c) converge
(d) diverge near the axis and converge near the periphery
