This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Psychiatry
True aboutAutism -a) Persistent delusionb) Persistent hallucinationc) Incoordinate social interactiond) Defective reciprocal interactione) Onset after 5 yr 
Select and explain. 
A. ab, B. cd, C. bd, D. ac
B: cd
Answer: B: cd 
Explanation: "Autism i.e., marked impairment in reciprocal, social and interpersonal interaction"....... Ahuja
Onset of symptoms of autism is before 2.5-3 years.
There are no delusions or hallucinations.