This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Plague, Subject name: Social & Preventive Medicine
Plague is transmitted by all EXCEPT? 
Select and explain. 
A. X. Cheopsis, B. X. Astia, C. Pulexirritans, D. Culex
D: Culex
Answer: D: Culex 
Explanation: Ans. (d) CulexRef : K. Park 23rd ed. / 292-93* The commonest and most effective vector of plague is rat flea x.cheopsis.* Others are X.Astia, X.Brasiliensis and Pulexirritans.* Culex is a vector of lymphatic filariasis and Japanese encephalitis (culex tritaeniorhynchus).