Answer:
Flat worm.have flat bodies be wise they lack true body cavity or body fluid cavity.
They have incomplete digestive system with one opening which make them to absorb food easily.
Their shape allow easy diffussion of gases i.e take in oxygen and eliminating carbondioxide because they lack circulatory system
They have reproduction success because they are hermaphrodite.
Step-by-step explanation:
Flat worm worms are organisms that live in water or moist environment. They have flat shape. They lack circulatory system, they have no true body cavity and they are hermaphrodites. Some are free living while others are parasitic. Examples include blood fluke, tapeworm. They are bilateral symmetrical.