(a) Spherical, The point source emits the spherical wavefront as the light diverges from a point source in all directions.(b) Planar, The shape of the wavefront in case of a light emerging out of a convex lens when a point source is placed at its focus is a parallel grid.(c) Planar, (A small area on the surface of a large sphere is nearly planar). The portion of the wavefront of light from a distant star intercepted by the Earth is a plane.