This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Yersinia, Subject name: Microbiology
Reservoir of plagu e is - 
Select and explain. 
A. Domestic rat, B. Wild rat, C. Rat flea, D. Man
B: Wild rat
Answer: B: Wild rat 
Explanation: Ans. is -b' i.e., Wild rat Life cycle of plague bacilliReservoir of infection - Wild rodent (Tetra indica)Vector - Rat flea{Xenopsvlla cheopis in north IndiaXenopsylla astia in south India Modes of transmissionCommensalrats(Rattus rattus)|Rat flea|Man(Most common mode)Wild rodents|Wild rodent flea|Man|Wild rodents (Tetra Indica) peridomestic rodents (Rattus non'egicus). Commensal rodents (Rattus rattus)|Wild rodent fleas, peridomestic rodent fleas, commensal rodents fleas|ManMan|Human flea (pulex irritans)|ManMan|Man (In pneumonic plague)