This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Communicable Diseases, Subject name: Social & Preventive Medicine
[{'content': 'Rickettsial agent of Epidemic typhus is \nSelect and explain. \nA. R. prowazekii, B. R. typhi, C. R. tsutsugamushi, D. R. canorii', 'role': 'user'}, {'content': 'Answer: A \nExplanation: (R-prowazekii) (239-PK) (262- Park 20th)DiseaseRickettsial agentInsect vectorsMammalian reservoirsITyphus group a. Epidemic typhusR. prowazekiiLouseHumansb. Murine typhusR. typhiFleaRodentsc. Scrub typhusR. tsutsugamushiMiteRodentsIISpotted fever group a. Indian tick typhusR. conoriiTickRodents, dogsb. Rocky Mountain spotted feverR. rickettsiiTickRodents, dogsc. Rickettsial poxR. akariMiteMiceIIIOthers a. Q-feverC. burnetii-Cattle, sheep, goatsb. Trench feverRochalimaeaquintanaLouseHumans', 'role': 'assistant'}]