This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Proteins and Amino Acids, Subject name: Biochemistry
Enzyme deficiency in Alkaptonuria is 
Select and explain. 
A. Tyrosine hydroxylase, B. Homogentisate acid oxidase, C. Phenyl alanine hydroxylase, D. Cystathione synthase
B: Homogentisate acid oxidase
Answer: B: Homogentisate acid oxidase 
Explanation: B. i.e. (Homogentisate oxidase) (259 - Harper 27th)ALKAPTONURIA = lack of enzyme homogentisate oxidase enzyme most striking clinical manifestation - occurrence of dark urine black on standing in air*** Classical type Galactosemia - Galactose-1 p- uridyl transferase enzyme* Classical phenylketonuria - Phenyl alanine hydroxylase* Type I Tyrosinemia - Fumatyl acetoacetate hydrolase enzyme* Type II Tyrosinemia - Hepatic transaminase enzyme.