Given the question: Q: Fish are a diverse and interesting group of organisms in what sub-phylum? Read this paragraph and choose the correct option from the provided answers: If the word fish makes you think of cute little goldfish in a tank, check out the anglerfish pictured in Figure below . It's also called a black sea devil. Surprisingly, goldfish and angler fish aren't all that different from each other as far as fish diversity goes. Both fish are placed in the same fish class. Clearly, fish are a diverse and interesting group of vertebrates. Choices: - mammals - invertebrates - organelles - vertebrates A:
The answer is:
vertebrates