Intellectual disability is characterized by limitations in functioning that begin at what age?

Intellectual disability is characterized by significant limitations in both intellectual functioning and adaptive behavior, which include everyday social and practical skills. This condition typically manifests during the developmental period, which is identified as the time frame leading up to the age of 18.

The correct answer is based on the understanding that intellectual disabilities should be present before an individual reaches adulthood, specifically before the age of 18. This aligns with the diagnostic criteria utilized in the mental health and educational fields which state that the onset must occur during the developmental stage of life, which typically is considered to be up to the age of 18.

Identifying the age range is crucial for providing appropriate support and services to individuals with intellectual disabilities, as interventions are often most effective during these formative years.