<prompt> A 16-year-old male is found to have a mental age of 9 years on I.Q. testing. He hasMild mental RetardationModerate mental retardationSevere mental retardationProfound mental retardation  <response>: IQ is Mental age Chronological age multiplied by 100. Here is it 916 100 which is 56. IQ is classified as Mild 50-69, Moderate 35-49, Severe 20-34 and Profound 20. Ref: The ICD-10 Classification of behavioural and mental disorders, CDDG, pg 171. 