Natural habitat of Schistosoma (blood flukes):

Ans. is 'd' i.e., All of the above(Ref: Chatterjee, 12th/e, p. 136)* S. Haematobium - Veins of Vesical and Pelvic plexuses, less commonly in portal vein and its mesenteric branch.* S. Mansoni - Mesenteric veins draining Sigmoidorectal region (inferior mesenteric veins).* S. Japonicum - Mesenteric veins draining Ileocecal region (superior mesenteric vein).