The correct option is D Female organism
Schistosoma is a genus of trematodes, commonly called as blood-flukes and are parasitic flatworms responsible for a highly significant group of infections in humans. The Schistosomes are dioecious and display a strong sexual dimorphism. The male is considerably larger than the female. The male surrounds the female and encloses her within this gynacophoic canal for the entire adult lives of the worms, where they reproduce sexually.
So, the correct answer is option D.