Final answer:
Echoing what is said, engaging in stereotyped movements, and compulsive behaviors are indicative of Autism Spectrum Disorder (ASD), which involves a range of symptoms including impaired social skills and strict adherence to rituals.
Step-by-step explanation:
If a person echoes what is said to them, exhibits stereotyped movements, and engages in compulsive and ritualistic behavior, they most likely have Autism Spectrum Disorder (ASD). A characteristic symptom of ASD is impaired social skills, such as difficulty making and maintaining eye contact and reading social cues. Other symptoms include repetitive motor behaviors, strict adherence to certain rituals, and preoccupation with specific subjects. It is a spectrum disorder, meaning that it affects individuals differently, ranging from those with severe impairments to those who are highly functional with good-to-excellent language skills.