Pick all the correct statements about light rays reflecting off of spherical mirrors. a$.$ A ray travelling parallel to the optical axis of a spherical mirror is reflected along a line that goes through the focal point of the mirror. b$.$ A ray travelling along a line that goes through the focal point of a spherical mirror is reflected along a line parallel to the optical axis of the mirror. c$.$ A ray travelling along a line that goes through the center of curvature of a spherical mirror is reflected back along the same line. d$.$ A ray that strikes the vertex of a spherical mirror is reflected symmetrically about the optical axis of the mirror.