You find what you believe is a new species of animal. Which of the following characteristics would enable you to argue that it is more closely related to a flatworm than it is to a roundworm?

It has a cuticle that it sheds in order to grow.

Its larvae have cilia that they use for feeding and locomotion.

It is shaped like a worm.

It has a well-developed coelom.

Its larvae have cilia that they use for feeding and locomotion.

Explanation:

Flatworms or platyhelminths are simple organisms with bilateral symmetry. Their body is unsegmented and soft with different shapes. Flatworms don't have body cavity, have no specialized circulatory and respiratory organs. There are four main groups of them: Turbellaria, which are mostly non-parasitic animals such as planarians, Cestoda, Trematoda and Monogenea (all three of them are parasitic groups).