A child presents with delayed physical and mental development. Biochemical testing detects increased levels of a certain keto acid in child’s urine that produces a qualitative color reaction with ferric chloride. What hereditary disease does this child have?

• A. Hyperthyroidism
• B. Cystinuria
• C. Hepatitis
• D. Diabetes mellitus
• E. Phenylpyruvic oligophrenia