You are answering a USMLE-style medical question. Question: A 33-year-old man presents to the infectious diseases clinic for follow-up. He was recently admitted to the hospital with fever, shortness of breath, and cough, and was found to have Pneumocystic jirovecii pneumonia and a new diagnosis of HIV. His CD4 count is 175, viral load is pending. As part of routine laboratory studies given his new diagnosis, an RPR was found to be positive with a titer of 1:64, and this is confirmed with a positive FTA-ABS. He is unsure when or how he acquired HIV or syphilis. His neurological examination is normal, and he has no symptoms. Which of the following is the most appropriate next step in management: Options: A) Perform lumbar puncture, treat based on presence or absence of CNS disease B) Treat with three weekly injections of penicillin, obtain titers in 3 months C) Treat with three weekly injections of penicillin, obtain titers in 6 months D) Treat with a single injection of penicillin, obtain titers in 6 months Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.