<prompt> Which of the following inborn errors of metabolism is associated with mental retardation -AlkaptonuriaHomocystinuriaPentosuriaAll  <response>: Ans. is b i.e., Homocystinuria Metabolic disorders associated with mental retardation. i Aminoaciduria Phenylketonuria, homocystinemia, histidinemia ii Galactosemia iii Mucopolysaccharidosis 