<prompt> Viruses causing hemorrhagic fever are:Lassa fever virusYellow fever virusWest Nile virusCrimean Congo virus  <response>: Ans. are b and d i.e., Yellow fever virus, Crimean Congo virusRef: Ananthanarayan, 9the, p. 522, 523 and 8the, p. 520 Group B arboviruses are JE, Dengue, Westnile virus,Yellow fever and KFD. Other Viruses causing hemorrhagic fever are - Kyasanur forest disease virus, Omsk hemorrhagic fever virus, Crimean Congo hemorrhagic fever virus. 