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: Microbiology
Congenital syphilis can be best diagnosed by: 
Select and explain. 
A. IgM FTAabs, B. IgG FTAabs, C. VDRL, D. TPI
A: IgM FTAabs
Answer: A: IgM FTAabs 
Explanation: IgM-FTA-Abs test is a modification to identify fetal IgM and clarify the diagnosis of congenital syphilis or a re-infection. Ref: Color Atlas of Dermatology By Main Rocken, Main Schaller - 2012