This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of nucleic acids, Subject name: Biochemistry
[{'content': 'The relationship between sulphonamide and PABA is \nSelect and explain. \nA. Metabolic antagonism, B. Synergism, C. Intermediate compound formation, D. Chelation', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Sulfonamides have structural similarity with PABA .therefore, they competitively inhibit the enzyme responsible for the incorporation of PABA into dihydropteroic acid, the immediate precursor of folic acidRef: DM Vasudevan, 7th edition, page no: 491, 61', 'role': 'assistant'}]