The refractive index of the material of a prism is √2 and its refracting angle is 30º. One of the refracting surfaces of the prism is made a mirror inwards. A beam of monochromatic light enters the prism from the mirrored surface if its angle of incidence of the prism is
(a) 30º (b) 45º (c) 60º (d) 0º