This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteriology, Subject name: Medicine
[{'content': 'Best confirmatory serological test for syphilis is? \nSelect and explain. \nA. VDRL, B. TPPA, C. TPHA, D. FTA-ABS', 'role': 'user'}, {'content': 'Answer: D \nExplanation: ANSWER: (D) FTA-ABSREF: Harrison 17th ed chapter 162 table 162-1Repeat Medicine Post diploma June 2012', 'role': 'assistant'}]