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: Unknown
The enzyme deficient in Galactosemia is: 
Select and explain. 
A. Hexoseaminidase B, B. Hexosaminidase A, C. Galactose 1 phosphate uridyltransferase, D. Glucocerebrosidase
C: Galactose 1 phosphate uridyltransferase
Answer: C: Galactose 1 phosphate uridyltransferase 
Explanation: Ref. Textbook of Biochemistry for Medical Students. Page. 183
Galactosemia is an autosomal recessive trait that results from a defective gene encoding either galactokinase or galactose 1-P uridyltransferase. 

There are over 100 heritable mutations that can cause galactosemia, and the incidence is approximately 1 in 60,000 births.
Galactose will be present in elevated amounts in the blood and urine and can result in decreased glucose synthesis and hypoglycemia.
Galactosemia symptoms often begin around day 3 in a newborn and include the hallmark cataracts.
Jaundice and hyperbilirubinemia do not resolve if the infant is treated with phototherapy
Severe bacterial infections ( E.coli sepsis) are common in untreated galactosemic infants. Failure to thrive, lethargy, hypotonia, and mental retardation are other common and apparent features