Question: Why might tapeworms and flukes have complex reproductive cycles, but other body systems are reduced or absent? Need Assignment Help? O A. This is an adaptation to a parasitic lifestyle. O B. Within each species, different worms are specialized for different functions and cooperate as a group. O C. There is no room in the body for other organ systems. O D. Their lifespan is usually short, with some tapeworms and flukes living for only 1-2 days.