Among invertebrates, which possesses the greatest power of regeneration?

Explanation

Sponges can repair their body parts, even if a large part is lost. Sponges can regenerate the entire organism from the conglomeration of their cells. In Planaria, mainly the head or tail is regenerated in decapitated flatworms (some species). It is a fundamental concept in biology that the more complex an animal, the lesser is its power of regeneration. Therefore, echinoderms have the least power of regeneration and sponges have the greatest power of regeneration.