Which muscle is contracted as pa of the pupillary light reflex?: (A) Ciliary muscle, (B) Pupillary dilator muscle, (C) Pupillary sphincter muscle, (D) Radial fibers of the iris
Answer is C. In a normal individual, shining a light in either eye will result in both pupils constricting due to contraction of the pupillary sphincter muscles. In contrast, the pupillary dilator muscle dilates the pupil. The ciliary muscle is involved in focusing the eye (accommodation).