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: Pediatrics
Which of the following inborn errors of metabolism is associated with mental retardation –a)  Alkaptonuriab)  Homocystinuriac)  Pentosuriad)  Galactosemia 
Select and explain. 
A. c, B. d, C. bd, D. ac
C: bd
Answer: C: bd 
Explanation: Metabolic disorders associated with mental retardation.

Aminoaciduria —› Phenylketonuria, homocystinemia, histidinemia
Galactosemia
Mucopolysaccharidosis