An initially parallel cylindrical beam travels in a medium of refractive index $\mu(I) = \mu_0 + \mu_2I$, where $\mu_0$ and $\mu_2$ are positive constants and $I$ is the intensity of the light beam. The intensity of the beam is decreasing with increasing radius. <br> <br> Question : As the beam enters the medium, it will

Question

( A ) diverge near the axis and converge near the periphery
( B ) travel as a cylindrical beam
( C ) converge
( D ) diverge