Any birth which occurs 35 or fewer weeks after conception is considered to be

If you were a participant in a developmental study that was using a(n) __________ design, you would expect to be repeatedly observed and tested over time, often for many years

FIll in the blank with correct word.

In the majority of cases, the cause of mental retardation is ______

a. clearly identified genetic abnormalities b. unknown c. poor prenatal nutrition d. prenatal drug abuse by the mother