Definition: Given a scientific passage and an answer, generate a question for the given answer.
Input: Passage: Do you know what these greenish, blob-like shapes are? Would it surprise you to learn that they are animals? They don't look anything like the animals you are probably familiar withanimals such as dogs and deer, fish and frogs. But the greenish blobs are animals nonetheless. They belong to a phylum called Cnidaria, but you may know them as jellyfish. They are very simple animals and not fish at all. Answer: cnidaria
Output:
Jellyfish belong to which phylum?