The Wilsons note that their 6-month-old daughter Beth seems to be developing more slowly and is not as playful as other infants her age. Research suggests that

answer choices
Beth's IQ will be below average in childhood but not necessarily in adulthood.

Beth's IQ will be below average in both childhood and adulthood.

observations of Beth's early behavior may be highly predictive of the later development of Down syndrome.

casual observations of Beth's behavior cannot be used to predict her later IQ.