Question

The phylogenetic tree of animals shows that

• A. cnidaria evolved from sponges
• B. flatworms evolved from roundworms
• C. both sponges and cnidaria evolved from protoctista
• D. all of the above

Answer 1

The correct option is C both sponges and cnidaria evolved from protoctista

Phylogenetically both sponges and Cnideria can be said to have evolved from protists. This is because sponges lack some features found in other animals [e.g., epithelia with belt desmosomes and their choanocytes superficially resemble choanoflagellates (protozoan). An ancient line of sponges evolved into a more advanced group - the Cnidarians.

So, the correct option is 'both sponges and cnidaria evolved from protista'.