Your sister who lives in another state sends via e-mail photographs of her 6-month-old infant. You note the child has a white reflection from one of his eyes. You hastily assist in arranging an urgent pediatric ophthalmologic evaluation. Your sister immediately accesses the Internet and begins to ask questions of you. Which of the following statements found by your sister is correct?
a) This is a normal finding in newborns.
b) It is caused by an opacity of the lens.
c) It is indicative of amblyopia.
d) It may be a sign of retinoblastoma.