Question

question 43
flatworms are most closely related to the ______.
○ sponges
○ cnidarians
○ roundworms
○ annelids

Explanation:

Flatworms (Platyhelminthes) and roundworms (Nematoda) are both part of the group of animals known as worms. Sponges (Porifera) are simple, sessile animals with a different body plan. Cnidarians (like jellyfish) have a radial symmetry and stinging cells. Annelids (segmented worms) have a more complex segmented body structure. Flatworms and roundworms are both unsegmented worms and share some similarities in their basic body plan compared to the other options.

Answer:

roundworms