This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pneumonia, Subject name: Medicine
[{'content': 'A 50-year-old HIV-positive male comes to OPD wit complaints of fever and breathlessness . He is diagnosed as a case of Pneumocystis jiroveci pneumonia (PCP). At what CD4 T cell % ,primary prophylaxis for this condition is recommended to be staed? \nSelect and explain. \nA. < 20%, B. < 5%, C. <15%, D. <10%', 'role': 'user'}, {'content': 'Answer: A \nExplanation: NIH/CDC/IDSA Guidelines for the Prevention of Oppounistic Infections in Persons Infected with HIV PATHOGEN INDICATIONS FIRST CHOICE(S) ALTERNATIVES Pneumocystis jirovecii CD4+ T cell count <200/mL or Oropharyngeal candidiasis or Prior bout of PCP Trimethoprim-sulfamethoxazole (TMP-SMX), 1 DS tablet qd PO or TMP-SMX, 1 SS tablet qd PO Dapsone 50 mg bid PO or 100 mg/d POor Dapsone 50 mg/d PO +Pyrimethamine 50 mg/week PO + Leucovorin 25 mg/week PO or (Dapsone 200 mg PO +Pyrimethamine 75 mg PO +Leucovorin 25 mg weekly PO) or Aerosolized pentamidine, 300 mg Respirgard II nebulizer every monthor Atovaquone 1500 mg/d POor TMP-SMX 1 DS tablet 3x/week PO May stop prophylaxis if CD4+ T cell count >200/mL for >=3 months', 'role': 'assistant'}]