This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: parasitology, Subject name: Microbiology
The definitive host for echinococcous granulosus is - 
Select and explain. 
A. Man, B. Sheep, C. Fox, D. Dog
D: Dog
Answer: D: Dog 
Explanation: Dog ,wolf ,jackal,fox etc can act as definitive host...but the optimal one is dog Sheep and cattle can act as intermediate host. Ref: panikers textbook of Medical parasitology 8th edition page 130