Assertion: A patient with phenylketonuria has skin pigmentation, mental retardation, and reduction in hair

Reason: In phenylketonuria, phenylalanine is converted into tyrosine which leads to absence of phenylalanine in the body

The correct option is C Assertion is true but the reason is false
Phenylketonuria is an autosomal recessive disorder. The homozygous recessive individuals lack an enzyme called phenylalanine hydroxylase which converts phenylalanine to tyrosine in the liver. The absence of this enzyme leads to the accumulation of phenylalanine in the body causing skin pigmentation, mental retardation, and loss of hair. So, the assertion is true but the reason is false.