Which of the following is not required for a DSM-5 diagnosis of intellectual disability (intellectual developmental disorder)?
A. Full-scale IQ below 70.
B. Deficits in intellectual functions confirmed by clinical assessment.
C. Deficits in adaptive functioning that result in failure to meet developmental
and sociocultural standards for personal independence and social responsibility.
D. Symptom onset during the developmental period.
E. Deficits in intellectual functions confirmed by individualized, standardized
intelligence testing.