The most common form of intellectual developmental disorder is ______ and the second most common form is ______.
A) Klinefelter's syndrome, Turner's syndrome
B) Down syndrome, Klinefelter's syndrome
C) fragile X syndrome, Down syndrome
D) Down syndrome, Fragile X syndrome

Question

Quizplus · Accepted Answer

Down syndrome is the most common form of intellectual developmental disorder, affecting approximately 1 in 700 births. Fragile X syndrome is the second most common form, affecting approximately 1 in 4,000 births. Klinefelter's syndrome and Turner's syndrome are genetic conditions, but they are not typically classified as intellectual developmental disorders.

The Most Common Form of Intellectual Developmental Disorder Is ______