The type of transmission involved in the case of plague in rat flea-: (A) Propagative, (B) Cyclo propagative, (C) Cyclo-Developmental, (D) None
Answer is A. propagative life cycle is the one in which the agent merely multiplies in vector ,but no change in form that is in the case of plague bacilli in rat fleas.parks textbokk,22 nd ed,pg no 94