-The phylum Mollusca represents the animals that have an unsegmented and a soft body.

What animals are soft-bodied?

This include animals such as earthworms, jellyfish, tapeworms, squids and an enormous variety of animals from almost every part of the kingdom Animalia.

What are Unsegmented animals?

The unsegmented animals with soft bodies are known as Platyhelminthes. Platyhelminthes (platy, meaning "flat" and helminth-, meaning "worm") are a phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrates. For example, tapeworm, flukes, Planarians, etc. So, the correct answer is 'Platyhelminthes.'