Question

which group of organisms has the derived characteristics of true tissues, bilateral symmetry, and a pseudocoelom?
sponges
roundworms
annelids
chordates

Explanation:

1. Sponges lack true tissues and symmetry, so they are eliminated.
2. Annelids and chordates have a true coelom, not a pseudocoelom, so they are eliminated.
3. Roundworms (nematodes) branch from the node with true tissues and bilateral symmetry, and are defined by the derived trait of a pseudocoelom, matching all three characteristics.

Answer:

roundworms