Intellectual disability originates during the developmental period and is defined by subaverage intellectual functioning with adaptive deficits. In which period does it originate?

• A. Infancy
• B. Developmental period
• C. Adolescence
• D. Adulthood

Answer: (B)

Intellectual disability is defined by subaverage intellectual functioning with adaptive deficits that begin during the developmental period. The crucial point is when the condition starts—it must originate before age 18, during development. This timing distinguishes intellectual disability from conditions that can occur later in life, like dementia or brain injuries, which are not classified as intellectual disabilities. The developmental period spans from birth through adolescence, so the onset is tied to those early life years rather than adulthood. That's why the correct framing is that it originates during the developmental period.