This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: D.O.C, Subject name: Pharmacology
[{'content': 'Drug of choice for syphilis - \nSelect and explain. \nA. Penicillin, B. Rifampicin, C. Tetracycline, D. Erythromycin', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e.. Penicillin InfectionChemoprophylaxis (DOC)InfectionChemoprophylaxis (DOC)o Cholera -TetracyclineMeningococci -Rifampicin (sulfadiazineo Plague -Tetracycline if strain is sensitive)o P.carinii -CotrimoxazoleDiphtheria -Erythromycino Whooping cough -ErythromycinBacterial conjuctivits -Erythromycin ointmento Toxoplasmosis -CotrimoxazoleTB -INHo Influenza -AmantadineMAC -Clarithromycin.''Azithromycino Rickettsia -TetracyclinesMalaria -Chloroquineo Bird flu- OseltamivirSurgical prophylaxis -Cefazolino Gonorrhoes/syphilis-Procaine penicillin", 'role': 'assistant'}]