________ is a congenital disease caused by a defect in the metabolism of the amino acid phenylalanine. The unmetabolized protein accumulates in the bloodstream. If undetected and untreated, it will result in mental retardation.
A. Microhematocrit
B. Polycythemia
C. Phenylketonuria
D. Neutrophil
Answer: C
Health Professions