Which of the following best describes the essential features of Autism Spectrum Disorder?

• A. Deficits in social communication and social interaction; restricted, repetitive patterns of behavior, interests, or activities; onset in the early developmental period; impairment; not better explained by another disorder.
• B. A mood disorder characterized by episodes of mania and hypomania lasting at least one week.
• C. A disorder marked by persistent fear of social situations leading to avoidance without core sensory or communication deficits.
• D. A sleep-wake disorder presenting with difficulty initiating and maintaining sleep.

Answer: (A)