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: Skin
[{'content': 'Which of the following is not a test for syphilis: September 2011 \nSelect and explain. \nA. VDRL, B. Frei test, C. TPHA, D. FTA-Abs', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B: Frei test Frei test is an obsolete intradermal test done for lymphogranuloma venerum', 'role': 'assistant'}]