Answer: 3. New individuals develop from pieces that break off an individual. (Fragmentation)
Step-by-step explanation:
Sponges reproduce sexually as well as asexually. Fragmentation, in which a piece of the sponge breaks off, settles on a new substrate, and develops into a new individual, or budding is the two most common methods of asexual reproduction (a genetically identical outgrowth grows from the parent and eventually detaches or remains attached to form a colony). Only freshwater sponges engage in an unusual form of asexual reproduction that results in the development of gemmules. Gemmules are structures made by adult sponges that are resistant to the environment (e.g., in the freshwater sponge Spongilla). In gemmules, a pneumatic cellular layer that may be fortified with spicules surrounds an inner layer of archeocytes (amoebocytes).