This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: HAEM synth and porphyrias, Subject name: Biochemistry
[{'content': 'Most common porphyria in humans is due to deficiency of which of the following enzyme: \nSelect and explain. \nA. PBG deaminase, B. Uroporphyrinogen decarboxylase, C. Ferrochelatase, D. Coproporphyrinogen oxidase', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Porphyria Cutanea Tarda is the most common porphyria. Enzyme defect:- Uroporphyrinogen decarboxylase Sporadic (type 1) Familial (type 2) Can also develop after exposure to halogenated aromatic hydrocarbons. MC Acute porphyria - Acute intermittent porphyria MC porphyria in children - Erythropoietic protoporphyria', 'role': 'assistant'}]